diff --git a/.gitignore b/.gitignore
index 66e482551..2a1a5fd2c 100644
--- a/.gitignore
+++ b/.gitignore
@@ -13,6 +13,7 @@ _site
 .sass-cache
 .jekyll-metadata
 public/
+tests/public_test/
 node_modules/
 _gen/
 .hugo_build.lock
diff --git a/config/_default/params.yaml b/config/_default/params.yaml
index 90adbd391..9b7c6ffef 100644
--- a/config/_default/params.yaml
+++ b/config/_default/params.yaml
@@ -166,9 +166,6 @@ ui:
   # Sidebar generation is slow otherwise
   sidebar_cache_limit: 100
 
-  # We have almost 200 attributes; don't truncate the sidebar to max 50 contents.
-  sidebar_menu_truncate:  0
-
   #  Set to true to disable breadcrumb navigation.
   breadcrumb_disable: false
   
diff --git a/config/testing/hugo.yaml b/config/testing/hugo.yaml
new file mode 100644
index 000000000..f625566c3
--- /dev/null
+++ b/config/testing/hugo.yaml
@@ -0,0 +1,50 @@
+# Hugo testing environment configuration
+#
+# Used exclusively when running the bibliography JSON-LD test suite:
+#
+#   hugo --environment testing --destination tests/public_test
+#
+# This environment mounts the test fixtures from tests/fixtures/bibliography/
+# alongside the real bibliography content, so the JSON-LD template is exercised
+# against controlled data without those pages ever appearing in a production build.
+#
+# The module.mounts block must re-declare all standard project-level mounts
+# because adding any mount replaces Hugo's defaults for the project.
+# Theme (Docsy) mounts defined within that module are unaffected.
+
+baseURL: "http://localhost/"
+
+publishDir: tests/public_test
+
+# Broken refs in unrelated content files must not block the test build.
+refLinksErrorLevel: WARNING
+
+# Explicit mounts (see module section below) require this to be re-stated
+# so that English content URLs do not gain an /en/ prefix.
+defaultContentLanguageInSubdir: false
+
+module:
+  mounts:
+    # ── Standard project mounts (preserve defaults) ──────────────────────────
+    # Mount content/en/ directly as the English language content root so that
+    # URLs are generated without an /en/ prefix (matching production behavior).
+    - source: content/en
+      target: content
+      lang: en
+    - source: static
+      target: static
+    - source: layouts
+      target: layouts
+    - source: data
+      target: data
+    - source: assets
+      target: assets
+    - source: i18n
+      target: i18n
+    - source: archetypes
+      target: archetypes
+    # ── Test fixtures ─────────────────────────────────────────────────────────
+    # Mount alongside the real bibliography content for the English language.
+    - source: tests/fixtures/bibliography
+      target: content/history/bibliography
+      lang: en
diff --git a/content/en/history/bibliography/_index.md b/content/en/history/bibliography/_index.md
index a4ad1df13..4a4998312 100644
--- a/content/en/history/bibliography/_index.md
+++ b/content/en/history/bibliography/_index.md
@@ -4,6 +4,7 @@ heading: Interlisp Bibliography
 type: bibliography
 cascade:
     type: bibliography
+    toc_hide: true
 weight: 5
 aliases:
  - /bibliography/
diff --git a/layouts/_partials/bibliography-date.html b/layouts/_partials/bibliography-date.html
new file mode 100644
index 000000000..69c1bc9c5
--- /dev/null
+++ b/layouts/_partials/bibliography-date.html
@@ -0,0 +1,27 @@
+{{- /*
+  bibliography-date.html
+  Resolves a bibliography page's publication date.
+
+  The front-matter `date` param is a plain YYYY-MM-DD string produced by
+  bibSplit.pl. Hugo's built-in .Date can be a full datetime parsed from git
+  history; this partial prefers the explicit param when it is well-formed.
+
+  Accepts: page context (.)
+  Returns: dict
+    dateISO   – YYYY-MM-DD string; "0001-01-01" when no date is known
+    hasDate   – true when dateISO is not the zero value
+    dateLabel – .Params.readabledate when present, otherwise dateISO
+*/ -}}
+{{- $dateTime := .Date -}}
+{{- with .Params.date -}}
+  {{- $iso := trim . " " -}}
+  {{- if and (ne $iso "") (findRE `^\d{4}-\d{2}-\d{2}$` $iso) -}}
+    {{- $dateTime = time $iso -}}
+  {{- end -}}
+{{- end -}}
+{{- $dateISO := $dateTime.Format "2006-01-02" -}}
+{{- return dict
+  "dateISO"   $dateISO
+  "hasDate"   (ne $dateISO "0001-01-01")
+  "dateLabel" (or .Params.readabledate $dateISO)
+-}}
diff --git a/layouts/_partials/bibliography-json-ld.html b/layouts/_partials/bibliography-json-ld.html
index b466452ff..1cbbec255 100644
--- a/layouts/_partials/bibliography-json-ld.html
+++ b/layouts/_partials/bibliography-json-ld.html
@@ -11,18 +11,13 @@
 */ -}}
 {{- if eq .Type "bibliography" -}}
 
+{{- /* ── Date (resolved once, used by the IsPage branch below) ───────────── */ -}}
+{{- $date := partial "bibliography-date.html" . -}}
+
 {{- if .IsPage -}}
 
-{{- /* ── Date: mirror the logic in single.html ──────────────────────────── */ -}}
-{{- $dateTime := .Date -}}
-{{- with .Params.date -}}
-  {{- $iso := trim . " " -}}
-  {{- if and (ne $iso "") (findRE `^\d{4}-\d{2}-\d{2}$` $iso) -}}
-    {{- $dateTime = time $iso -}}
-  {{- end -}}
-{{- end -}}
-{{- $dateISO := $dateTime.Format "2006-01-02" -}}
-{{- $hasDate  := ne $dateISO "0001-01-01" -}}
+{{- $dateISO := $date.dateISO -}}
+{{- $hasDate := $date.hasDate -}}
 
 {{- /* ── Map item_type → Schema.org @type ──────────────────────────────── */ -}}
 {{- $itemType   := .Params.item_type | default "document" -}}
@@ -91,11 +86,36 @@
 {{- with .Params.url_source -}}{{- $sameAs = append (trim . " ") $sameAs -}}{{- end -}}
 {{- with .Params.zotero_url -}}{{- $sameAs = append (trim . " ") $sameAs -}}{{- end -}}
 
+{{- /* ── CS Concepts: about[] + keywords[] ────────────────────────────
+     Reads the `concepts:` list from front matter (list of concept IDs).
+     Looks each ID up in data/bibliography/concepts.json to get the name.
+     Emits schema:about (array of DefinedTerm) and schema:keywords (string).
+*/ -}}
+{{- $conceptData   := site.Data.bibliography.concepts -}}
+{{- $conceptIds    := .Params.concepts -}}
+{{- $aboutObjs     := slice -}}
+{{- $keywordNames  := slice -}}
+{{- if reflect.IsSlice $conceptIds -}}
+  {{- range $conceptIds -}}
+    {{- $id      := trim . " " -}}
+    {{- $concept := index $conceptData $id -}}
+    {{- if $concept -}}
+      {{- $aboutObjs    = append (dict
+            "@type"          "DefinedTerm"
+            "@id"            (printf "https://interlisp.org/concepts/#%s" $id)
+            "name"           $concept.name
+            "inDefinedTermSet" "https://interlisp.org/data/cs-concepts.jsonld"
+          ) $aboutObjs -}}
+      {{- $keywordNames = append $concept.name $keywordNames -}}
+    {{- end -}}
+  {{- end -}}
+{{- end -}}
+
 {{- /* ── Base JSON-LD object (properties common to all types) ─────────── */ -}}
 {{- $ld := dict
   "@context"   "https://schema.org"
   "@type"      $schemaType
-  "name"       .Title
+  "name"       (.Title | strings.TrimRight "\n ")
   "url"        .Permalink
   "inLanguage" "en-US"
 -}}
@@ -124,6 +144,14 @@
   {{- $ld = merge $ld (dict "sameAs" $sameAs) -}}
 {{- end -}}
 
+{{- if gt (len $aboutObjs) 0 -}}
+  {{- $ld = merge $ld (dict "about" $aboutObjs) -}}
+{{- end -}}
+
+{{- if gt (len $keywordNames) 0 -}}
+  {{- $ld = merge $ld (dict "keywords" (delimit $keywordNames ", ")) -}}
+{{- end -}}
+
 {{- /* ── Patent: additionalType + structured identifiers ──────────────── */ -}}
 {{- if eq $itemType "patent" -}}
   {{- $ld = merge $ld (dict "additionalType" "Patent") -}}
@@ -140,10 +168,10 @@
   {{- end -}}
 
   {{- with .Params.assignee -}}
-    {{- $ld = merge $ld (dict "funder" (dict "@type" "Organization" "name" .)) -}}
+    {{- $ld = merge $ld (dict "copyrightHolder" (dict "@type" "Organization" "name" .)) -}}
   {{- end -}}
   {{- with .Params.issuing_authority -}}
-    {{- $ld = merge $ld (dict "countryOfOrigin" (dict "@type" "Country" "name" .)) -}}
+    {{- $ld = merge $ld (dict "validIn" (dict "@type" "DefinedRegion" "name" .)) -}}
   {{- end -}}
 {{- end -}}
 
@@ -160,11 +188,14 @@
 {{- /* ── Conference paper ─────────────────────────────────────────────── */ -}}
 {{- if eq $itemType "paper-conference" -}}
   {{- with .Params.proceedings_title -}}
-    {{- $ld = merge $ld (dict "isPartOf" (dict "@type" "Periodical" "name" .)) -}}
+    {{- $ld = merge $ld (dict "isPartOf" (dict "@type" "Book" "name" .)) -}}
   {{- end -}}
   {{- with .Params.publisher -}}
     {{- $ld = merge $ld (dict "publisher" (dict "@type" "Organization" "name" .)) -}}
   {{- end -}}
+  {{- with .Params.place -}}
+    {{- $ld = merge $ld (dict "locationCreated" (dict "@type" "Place" "name" .)) -}}
+  {{- end -}}
 {{- end -}}
 
 {{- /* ── Book ─────────────────────────────────────────────────────────── */ -}}
@@ -172,9 +203,6 @@
   {{- with .Params.publisher -}}
     {{- $ld = merge $ld (dict "publisher" (dict "@type" "Organization" "name" .)) -}}
   {{- end -}}
-  {{- with .Params.place -}}
-    {{- $ld = merge $ld (dict "locationCreated" .) -}}
-  {{- end -}}
 {{- end -}}
 
 {{- /* ── Chapter ──────────────────────────────────────────────────────── */ -}}
@@ -194,10 +222,10 @@
   {{- with .Params.publisher -}}
     {{- $ld = merge $ld (dict "publisher" (dict "@type" "Organization" "name" .)) -}}
   {{- end -}}
-  {{- with .Params.reportType -}}
+  {{- with .Params.report_type -}}
     {{- $ld = merge $ld (dict "additionalType" .) -}}
   {{- end -}}
-  {{- with .Params.reportNumber -}}
+  {{- with .Params.report_number -}}
     {{- $ld = merge $ld (dict "identifier" (dict "@type" "PropertyValue" "propertyID" "report-number" "value" .)) -}}
   {{- end -}}
 {{- end -}}
@@ -243,15 +271,12 @@
   {{- end -}}
 {{- end -}}
 
-<script type="application/ld+json">
-{{- $ld | jsonify (dict "indent" "  ") | safeJS -}}
-</script>
+{{- printf "<script type=\"application/ld+json\">\n%s\n</script>" ($ld | jsonify (dict "indent" "  ")) | safeHTML -}}
 
 {{- else if .IsSection -}}
 
 {{- /* ── COLLECTION PAGE (bibliography index) ──────────────────────────── */ -}}
 {{- $pages := .RegularPages -}}
-{{- $pages  = sort $pages "Date" "desc" -}}
 {{- $pages  = sort $pages "Title" "asc" -}}
 
 {{- $itemList := slice -}}
@@ -281,9 +306,7 @@
   )
 -}}
 
-<script type="application/ld+json">
-{{- $ld | jsonify (dict "indent" "  ") | safeJS -}}
-</script>
+{{- printf "<script type=\"application/ld+json\">\n%s\n</script>" ($ld | jsonify (dict "indent" "  ")) | safeHTML -}}
 
 {{- end -}}
 
diff --git a/layouts/bibliography/single.html b/layouts/bibliography/single.html
index 62dd9a4e4..7f6a0a9be 100644
--- a/layouts/bibliography/single.html
+++ b/layouts/bibliography/single.html
@@ -30,18 +30,10 @@ <h1>{{ .Title }}</h1>
   </p>
 {{- end -}}
 <p>
-  {{- $dateTime := .Date -}}
-  {{- with .Params.date -}}
-    {{- $isoDate := trim . " " -}}
-    {{- if and (ne $isoDate "") (findRE `^\d{4}-\d{2}-\d{2}` $isoDate) -}}
-      {{- $dateTime = time $isoDate -}}
-    {{- end -}}
-  {{- end -}}
-  {{- $dateISO := $dateTime.Format "2006-01-02" -}}
-  {{- $dateLabel := or .Params.readabledate $dateISO -}}
+  {{- $date := partial "bibliography-date.html" . -}}
   {{- /* Don't display bogus date */ -}}
-  {{- if ne $dateISO "0001-01-01" -}}
-    <time datetime="{{ $dateISO }}">{{ $dateLabel }}</time>
+  {{- if $date.hasDate -}}
+    <time datetime="{{ $date.dateISO }}">{{ $date.dateLabel }}</time>
   {{- end -}}
 </p>
 <p>
diff --git a/scripts/bibSplit.pl b/scripts/bibSplit.pl
index 8a9b77be2..71ce637aa 100755
--- a/scripts/bibSplit.pl
+++ b/scripts/bibSplit.pl
@@ -58,10 +58,12 @@ sub sanitize_text {
 
   my $type = $obj->{type} // '';
 
-  # Titles can have colons and other special characters.  Place YAML keyword on one line
-  # and follow it with the title indented on subsequent line
+  # Titles can have colons and other special characters.  Use a YAML double-quoted scalar
+  # so the decoded value has no trailing newline (the literal-block `|` style would add one).
   my $itemTitle = sanitize_text($obj->{title} // '');
-  my $title = $itemTitle eq '' ? "title: ''" : "title: |\n  $itemTitle\n";
+  (my $escapedTitle = $itemTitle) =~ s/\\/\\\\/g;
+  $escapedTitle =~ s/"/\\"/g;
+  my $title = $itemTitle eq '' ? "title: ''" : "title: \"$escapedTitle\"";
 
   # Abstracts can be multi-line and  contain multiple paragraphs.  Place YAML keyword on
   # one line and follow it with the abstract indented on subsequent lines.
@@ -78,13 +80,13 @@ sub sanitize_text {
   my $itemAuthors = '';
   if (ref($obj->{authorsFormatted}) eq 'ARRAY' && @{$obj->{authorsFormatted}}) {
     $itemAuthors = "\n";
-    for my $a (@{$obj->{authorsFormatted}}) {
+    for my $author (@{$obj->{authorsFormatted}}) {
       # The encode_json is where extended unicode chars get corrupted, e.g., "Emanuelson, Pär"
       # There may be other things that now don't work!!
       # my $quoted = encode_json($a // '');
       # sanitize_text seems to handle them correctly
-      my $san = sanitize_text($a // '');
-      $itemAuthors .= "  - \"$san\"\n";
+      my $san_author = sanitize_text($author // '');
+      $itemAuthors .= "  - \"$san_author\"\n";
     }
     $itemAuthors =~ s/\n$//u;  # strip trailing newline
   }
@@ -92,11 +94,11 @@ sub sanitize_text {
   my $itemEditors = '';
   if (ref($obj->{editorsFormatted}) eq 'ARRAY' && @{$obj->{editorsFormatted}}) {
     $itemEditors = "\n";
-    for my $a (@{$obj->{editorsFormatted}}) {
+    for my $editor (@{$obj->{editorsFormatted}}) {
       # as above...
-      # my $quoted = encode_json($a // '');
-      my $san = sanitize_text($a // '');
-      $itemEditors .= "  - \"$san\"\n";
+      # my $quoted = encode_json($editor // '');
+      my $san_editor = sanitize_text($editor // '');
+      $itemEditors .= "  - \"$san_editor\"\n";
     }
     $itemEditors =~ s/\n$//u;  # strip trailing newline
   }
@@ -185,6 +187,7 @@ sub sanitize_text {
 
 $extraFields
 tags:
+concepts:
 url_source: $urlSource
 zotero_url: "https://www.zotero.org/groups/2914042/items/$key"
 
diff --git a/tests/fixtures/bibliography/ZTEST-BLOG.md b/tests/fixtures/bibliography/ZTEST-BLOG.md
new file mode 100644
index 000000000..02928951c
--- /dev/null
+++ b/tests/fixtures/bibliography/ZTEST-BLOG.md
@@ -0,0 +1,20 @@
+---
+title: "Test Blog Post"
+date: 2021-08-20
+readabledate: 2021-08-20
+type: bibliography
+item_type: post-weblog
+authors:
+  - "Blogger, Test"
+editors:
+abstract: |
+  A test abstract for a blog post used by automated test fixtures.
+
+blog_title: "Test Tech Blog"
+
+tags:
+url_source: "https://example.com/blog/post"
+zotero_url: "https://www.zotero.org/groups/test/items/ZTESTBLG"
+
+lastmod: 2023-08-01T00:00:00Z
+---
diff --git a/tests/fixtures/bibliography/ZTEST-BOOK.md b/tests/fixtures/bibliography/ZTEST-BOOK.md
new file mode 100644
index 000000000..b0ecd9b45
--- /dev/null
+++ b/tests/fixtures/bibliography/ZTEST-BOOK.md
@@ -0,0 +1,20 @@
+---
+title: "Test Book Title"
+date: 1995-01-01
+readabledate: 1995
+type: bibliography
+item_type: book
+authors:
+  - "Author, Test"
+editors:
+abstract: |
+  A test abstract for a book used by automated test fixtures.
+
+publisher: "Test Publisher"
+
+tags:
+url_source: "https://example.com/book"
+zotero_url: "https://www.zotero.org/groups/test/items/ZTESTBOOK"
+
+lastmod: 2022-01-01T00:00:00Z
+---
diff --git a/tests/fixtures/bibliography/ZTEST-CHAPTER.md b/tests/fixtures/bibliography/ZTEST-CHAPTER.md
new file mode 100644
index 000000000..5fee537bf
--- /dev/null
+++ b/tests/fixtures/bibliography/ZTEST-CHAPTER.md
@@ -0,0 +1,23 @@
+---
+title: "Test Chapter Title"
+date: 2000-01-01
+readabledate: 2000
+type: bibliography
+item_type: chapter
+authors:
+  - "Writer, Test"
+editors:
+  - "Editor, Test"
+abstract: |
+  A test abstract for a book chapter used by automated test fixtures.
+
+book_title: "Test Book of Chapters"
+publisher: "Chapter Publisher"
+pages: "100-120"
+
+tags:
+url_source: "https://example.com/chapter"
+zotero_url: "https://www.zotero.org/groups/test/items/ZTESTCHAP"
+
+lastmod: 2022-03-01T00:00:00Z
+---
diff --git a/tests/fixtures/bibliography/ZTEST-CONFERENCE.md b/tests/fixtures/bibliography/ZTEST-CONFERENCE.md
new file mode 100644
index 000000000..14cc9176d
--- /dev/null
+++ b/tests/fixtures/bibliography/ZTEST-CONFERENCE.md
@@ -0,0 +1,23 @@
+---
+title: "Test Conference Paper"
+date: 2019-07-20
+readabledate: 2019-07-20
+type: bibliography
+item_type: paper-conference
+authors:
+  - "Brown, Carol K."
+  - "White, David"
+editors:
+abstract: |
+  A test abstract for a conference paper used by automated test fixtures.
+
+proceedings_title: "Proceedings of the Test Conference 2019"
+publisher: "ACM"
+place: "San Francisco, CA"
+
+tags:
+url_source: "https://example.com/conference-paper"
+zotero_url: "https://www.zotero.org/groups/test/items/ZTESTCONF"
+
+lastmod: 2022-08-15T00:00:00Z
+---
diff --git a/tests/fixtures/bibliography/ZTEST-ENCYCLOPEDIA.md b/tests/fixtures/bibliography/ZTEST-ENCYCLOPEDIA.md
new file mode 100644
index 000000000..93a35792d
--- /dev/null
+++ b/tests/fixtures/bibliography/ZTEST-ENCYCLOPEDIA.md
@@ -0,0 +1,20 @@
+---
+title: "Test Encyclopedia Entry"
+date: 2003-01-01
+readabledate: 2003
+type: bibliography
+item_type: entry-encyclopedia
+authors:
+  - "Scholar, Test"
+editors:
+abstract: |
+  A test abstract for an encyclopedia entry used by automated test fixtures.
+
+encyclopedia_title: "Encyclopedia of Test Computing"
+
+tags:
+url_source: "https://example.com/encyclopedia/entry"
+zotero_url: "https://www.zotero.org/groups/test/items/ZTESTENC"
+
+lastmod: 2023-11-01T00:00:00Z
+---
diff --git a/tests/fixtures/bibliography/ZTEST-JOURNAL.md b/tests/fixtures/bibliography/ZTEST-JOURNAL.md
new file mode 100644
index 000000000..6d7bbd71a
--- /dev/null
+++ b/tests/fixtures/bibliography/ZTEST-JOURNAL.md
@@ -0,0 +1,27 @@
+---
+title: "Test Scholarly Article"
+date: 2020-03-15
+readabledate: 2020-03-15
+type: bibliography
+item_type: article-journal
+authors:
+  - "Smith, Alice J."
+  - "Jones, Bob"
+editors:
+abstract: |
+  A test abstract for a journal article used by automated test fixtures.
+
+publication_title: "Journal of Test Science"
+volume: "5"
+issue: "2"
+pages: "45-67"
+
+tags:
+url_source: "https://example.com/journal-article"
+zotero_url: "https://www.zotero.org/groups/test/items/ZTESTJNL"
+concepts:
+  - "Interlisp"
+  - "ProgrammingLanguages"
+
+lastmod: 2023-01-10T00:00:00Z
+---
diff --git a/tests/fixtures/bibliography/ZTEST-MAGAZINE.md b/tests/fixtures/bibliography/ZTEST-MAGAZINE.md
new file mode 100644
index 000000000..bb560eb1f
--- /dev/null
+++ b/tests/fixtures/bibliography/ZTEST-MAGAZINE.md
@@ -0,0 +1,23 @@
+---
+title: "Test Magazine Article"
+date: 2021-06-01
+readabledate: 2021-06-01
+type: bibliography
+item_type: article-magazine
+authors:
+  - "Doe, Jane"
+editors:
+abstract: |
+  A test abstract for a magazine article used by automated test fixtures.
+
+publication_title: "Computing Monthly"
+volume: "10"
+issue: "6"
+pages: "12-14"
+
+tags:
+url_source: "https://example.com/magazine-article"
+zotero_url: "https://www.zotero.org/groups/test/items/ZTESTMAG"
+
+lastmod: 2023-02-01T00:00:00Z
+---
diff --git a/tests/fixtures/bibliography/ZTEST-MESSAGE.md b/tests/fixtures/bibliography/ZTEST-MESSAGE.md
new file mode 100644
index 000000000..b75745e44
--- /dev/null
+++ b/tests/fixtures/bibliography/ZTEST-MESSAGE.md
@@ -0,0 +1,18 @@
+---
+title: "Test Personal Communication"
+date: 2012-07-04
+readabledate: 2012-07-04
+type: bibliography
+item_type: personal_communication
+authors:
+  - "Sender, Test"
+editors:
+abstract: |
+  A test abstract for a personal communication used by automated test fixtures.
+
+tags:
+url_source: "https://example.com/communication"
+zotero_url: "https://www.zotero.org/groups/test/items/ZTESTMSG"
+
+lastmod: 2023-12-01T00:00:00Z
+---
diff --git a/tests/fixtures/bibliography/ZTEST-NO-URLS.md b/tests/fixtures/bibliography/ZTEST-NO-URLS.md
new file mode 100644
index 000000000..fe6764125
--- /dev/null
+++ b/tests/fixtures/bibliography/ZTEST-NO-URLS.md
@@ -0,0 +1,21 @@
+---
+title: "Test Entry Without URLs"
+date: 2008-06-15
+readabledate: 2008-06-15
+type: bibliography
+item_type: report
+authors:
+  - "Nobody, Test"
+editors:
+abstract: |
+  A test abstract for a report with no external URLs, used to verify that
+  the sameAs field is omitted when neither url_source nor zotero_url is set.
+
+publisher: "Test Publisher"
+
+tags:
+url_source:
+zotero_url:
+
+lastmod: 2024-01-01T00:00:00Z
+---
diff --git a/tests/fixtures/bibliography/ZTEST-PATENT.md b/tests/fixtures/bibliography/ZTEST-PATENT.md
new file mode 100644
index 000000000..33c23e828
--- /dev/null
+++ b/tests/fixtures/bibliography/ZTEST-PATENT.md
@@ -0,0 +1,23 @@
+---
+title: "Test Patent for Widget"
+date: 2015-03-10
+readabledate: 2015-03-10
+type: bibliography
+item_type: patent
+authors:
+  - "Inventor, Test"
+editors:
+abstract: |
+  A test abstract for a patent used by automated test fixtures.
+
+assignee: "Test Corporation"
+application_number: "US12345678"
+patent_number: "US9876543B2"
+issuing_authority: "United States"
+
+tags:
+url_source: "https://patents.google.com/patent/US9876543B2"
+zotero_url: "https://www.zotero.org/groups/test/items/ZTESTPAT"
+
+lastmod: 2023-06-01T00:00:00Z
+---
diff --git a/tests/fixtures/bibliography/ZTEST-REPORT.md b/tests/fixtures/bibliography/ZTEST-REPORT.md
new file mode 100644
index 000000000..9cad7896b
--- /dev/null
+++ b/tests/fixtures/bibliography/ZTEST-REPORT.md
@@ -0,0 +1,20 @@
+---
+title: "Test Technical Report"
+date: 2005-09-01
+readabledate: 2005-09-01
+type: bibliography
+item_type: report
+authors:
+  - "Researcher, Test"
+editors:
+abstract: |
+  A test abstract for a technical report used by automated test fixtures.
+
+publisher: "Test Research Lab"
+
+tags:
+url_source: "https://example.com/report"
+zotero_url: "https://www.zotero.org/groups/test/items/ZTESTRPT"
+
+lastmod: 2023-04-01T00:00:00Z
+---
diff --git a/tests/fixtures/bibliography/ZTEST-SOFTWARE.md b/tests/fixtures/bibliography/ZTEST-SOFTWARE.md
new file mode 100644
index 000000000..c0ab51dc8
--- /dev/null
+++ b/tests/fixtures/bibliography/ZTEST-SOFTWARE.md
@@ -0,0 +1,19 @@
+---
+title: "Test Software"
+date: 2016-02-14
+readabledate: 2016-02-14
+type: bibliography
+item_type: software
+authors:
+  - "Developer, Test"
+  - "Singularity"
+editors:
+abstract: |
+  A test abstract for a software entry used by automated test fixtures.
+
+tags:
+url_source: "https://github.com/example/test-software"
+zotero_url: "https://www.zotero.org/groups/test/items/ZTESTSOFT"
+
+lastmod: 2023-10-01T00:00:00Z
+---
diff --git a/tests/fixtures/bibliography/ZTEST-THESIS.md b/tests/fixtures/bibliography/ZTEST-THESIS.md
new file mode 100644
index 000000000..bd41d49fc
--- /dev/null
+++ b/tests/fixtures/bibliography/ZTEST-THESIS.md
@@ -0,0 +1,20 @@
+---
+title: "Test Doctoral Thesis"
+date: 2010-05-01
+readabledate: 2010-05-01
+type: bibliography
+item_type: thesis
+authors:
+  - "Student, Test"
+editors:
+abstract: |
+  A test abstract for a doctoral thesis used by automated test fixtures.
+
+university: "Test University"
+
+tags:
+url_source: "https://example.com/thesis"
+zotero_url: "https://www.zotero.org/groups/test/items/ZTESTTHES"
+
+lastmod: 2023-05-01T00:00:00Z
+---
diff --git a/tests/fixtures/bibliography/ZTEST-VIDEO.md b/tests/fixtures/bibliography/ZTEST-VIDEO.md
new file mode 100644
index 000000000..6a3b08335
--- /dev/null
+++ b/tests/fixtures/bibliography/ZTEST-VIDEO.md
@@ -0,0 +1,22 @@
+---
+title: "Test Motion Picture"
+date: 2018-04-01
+readabledate: 2018-04-01
+type: bibliography
+item_type: motion_picture
+authors:
+  - "Director, Test"
+editors:
+abstract: |
+  A test abstract for a motion picture used by automated test fixtures.
+
+studio: "Test Film Studio"
+video_recording_format: "MP4"
+series_title: "Test Film Series"
+
+tags:
+url_source: "https://example.com/video"
+zotero_url: "https://www.zotero.org/groups/test/items/ZTESTVID"
+
+lastmod: 2023-09-01T00:00:00Z
+---
diff --git a/tests/fixtures/bibliography/ZTEST-WEBPAGE.md b/tests/fixtures/bibliography/ZTEST-WEBPAGE.md
new file mode 100644
index 000000000..220418fd5
--- /dev/null
+++ b/tests/fixtures/bibliography/ZTEST-WEBPAGE.md
@@ -0,0 +1,20 @@
+---
+title: "Test Web Page"
+date: 2022-11-15
+readabledate: 2022-11-15
+type: bibliography
+item_type: webpage
+authors:
+  - "Webber, Test"
+editors:
+abstract: |
+  A test abstract for a web page used by automated test fixtures.
+
+website_title: "Test Website"
+
+tags:
+url_source: "https://example.com/page"
+zotero_url: "https://www.zotero.org/groups/test/items/ZTESTWEB"
+
+lastmod: 2023-07-01T00:00:00Z
+---
diff --git a/tests/test_bibliography_jsonld.py b/tests/test_bibliography_jsonld.py
new file mode 100644
index 000000000..ecd11e92d
--- /dev/null
+++ b/tests/test_bibliography_jsonld.py
@@ -0,0 +1,863 @@
+"""
+tests/test_bibliography_jsonld.py
+==================================
+Validates the JSON-LD structured data emitted by
+``layouts/_partials/bibliography-json-ld.html`` for every Schema.org type
+used in the Interlisp bibliography.
+
+How it works
+------------
+Each ``ZTEST-*.md`` fixture in ``tests/fixtures/bibliography/`` is the
+**mock input**: it provides fully-controlled front-matter values that Hugo
+feeds into the template.  A test-environment Hugo build mounts those fixtures
+into the content tree without touching production content.  The tests then
+read the rendered ``tests/public_test/history/bibliography/<slug>/index.html``,
+extract the ``<script type="application/ld+json">`` block, and assert that the
+resulting JSON-LD object has the correct Schema.org ``@type`` and every
+type-specific field.
+
+Fixture files (mock inputs)
+---------------------------
+    tests/fixtures/bibliography/ZTEST-JOURNAL.md     -> article-journal
+    tests/fixtures/bibliography/ZTEST-MAGAZINE.md    -> article-magazine
+    tests/fixtures/bibliography/ZTEST-CONFERENCE.md  -> paper-conference
+    tests/fixtures/bibliography/ZTEST-BOOK.md        -> book
+    tests/fixtures/bibliography/ZTEST-CHAPTER.md     -> chapter
+    tests/fixtures/bibliography/ZTEST-REPORT.md      -> report
+    tests/fixtures/bibliography/ZTEST-THESIS.md      -> thesis
+    tests/fixtures/bibliography/ZTEST-PATENT.md      -> patent
+    tests/fixtures/bibliography/ZTEST-WEBPAGE.md     -> webpage
+    tests/fixtures/bibliography/ZTEST-BLOG.md        -> post-weblog
+    tests/fixtures/bibliography/ZTEST-VIDEO.md       -> motion_picture
+    tests/fixtures/bibliography/ZTEST-SOFTWARE.md    -> software
+    tests/fixtures/bibliography/ZTEST-ENCYCLOPEDIA.md -> entry-encyclopedia
+    tests/fixtures/bibliography/ZTEST-MESSAGE.md     -> personal_communication
+    tests/fixtures/bibliography/ZTEST-NO-URLS.md     -> (sameAs absent edge case)
+
+Hugo build
+----------
+The session-scoped ``_hugo_build`` fixture runs:
+
+    hugo --environment testing --destination tests/public_test
+
+The ``config/testing/hugo.yaml`` environment mounts ``tests/fixtures/bibliography/``
+into the content tree via Hugo module mounts.  Test output lands in
+``tests/public_test/``, which is gitignored and never deployed.
+
+A rebuild is triggered automatically when any template or fixture file is
+newer than the most recent test output file.  Set the environment variable
+``PYTEST_FORCE_HUGO_BUILD=1`` to force a rebuild regardless.
+
+Prerequisites
+-------------
+    pip install pytest    # only stdlib + pytest are required
+
+Usage
+-----
+    # From the repository root:
+    pytest tests/test_bibliography_jsonld.py -v
+
+    # Force a fresh Hugo test build before running:
+    PYTEST_FORCE_HUGO_BUILD=1 pytest tests/test_bibliography_jsonld.py -v
+"""
+
+import functools
+import json
+import os
+import subprocess
+from html.parser import HTMLParser
+from pathlib import Path
+
+import pytest
+
+# ---------------------------------------------------------------------------
+# Paths
+# ---------------------------------------------------------------------------
+
+REPO_ROOT = Path(__file__).parent.parent
+TEST_PUBLIC = REPO_ROOT / "tests" / "public_test"
+BIB_PUBLIC = TEST_PUBLIC / "history" / "bibliography"
+FIXTURES_DIR = REPO_ROOT / "tests" / "fixtures" / "bibliography"
+
+# Hugo lowercases the filename slug when generating URLs.
+FIXTURE_SLUGS = [
+    "ztest-journal",
+    "ztest-magazine",
+    "ztest-conference",
+    "ztest-book",
+    "ztest-chapter",
+    "ztest-report",
+    "ztest-thesis",
+    "ztest-patent",
+    "ztest-webpage",
+    "ztest-blog",
+    "ztest-video",
+    "ztest-software",
+    "ztest-encyclopedia",
+    "ztest-message",
+    "ztest-no-urls",
+]
+
+
+# ---------------------------------------------------------------------------
+# Staleness check
+# ---------------------------------------------------------------------------
+
+def _needs_rebuild() -> bool:
+    """Return True when the test output is absent or older than any source file.
+
+    Source files watched: all Hugo templates, the test fixtures, and the
+    testing environment config.  Controlled by the ``PYTEST_FORCE_HUGO_BUILD``
+    environment variable (any non-empty value forces a rebuild).
+    """
+    if os.environ.get("PYTEST_FORCE_HUGO_BUILD"):
+        return True
+
+    html_files = list(BIB_PUBLIC.rglob("index.html"))
+    if not html_files:
+        return True
+
+    oldest_output = min(f.stat().st_mtime for f in html_files)
+
+    watched = [
+        REPO_ROOT / "layouts",
+        REPO_ROOT / "config" / "testing",
+        FIXTURES_DIR,
+    ]
+    for source in watched:
+        for path in source.rglob("*"):
+            if path.is_file() and path.stat().st_mtime > oldest_output:
+                return True
+
+    return False
+
+
+# ---------------------------------------------------------------------------
+# HTML helper – extract <script type="application/ld+json"> blocks
+# ---------------------------------------------------------------------------
+
+
+class _JSONLDExtractor(HTMLParser):
+    """Pull raw text out of every ``application/ld+json`` script element."""
+
+    def __init__(self) -> None:
+        super().__init__()
+        self._in_jsonld: bool = False
+        self.blocks: list[str] = []
+        self._buf: list[str] = []
+
+    def handle_starttag(self, tag: str, attrs: list) -> None:
+        if tag == "script" and dict(attrs).get("type") == "application/ld+json":
+            self._in_jsonld = True
+            self._buf = []
+
+    def handle_endtag(self, tag: str) -> None:
+        if tag == "script" and self._in_jsonld:
+            self._in_jsonld = False
+            self.blocks.append("".join(self._buf))
+
+    def handle_data(self, data: str) -> None:
+        if self._in_jsonld:
+            self._buf.append(data)
+
+
+@functools.lru_cache(maxsize=None)
+def _load_jsonld(slug: str) -> dict:
+    """Return the Schema.org JSON-LD dict from the built bibliography page *slug*.
+
+    Results are cached so each fixture HTML file is read and parsed exactly
+    once per test session regardless of how many test methods reference it.
+
+    Skips (not fails) when the built page is absent; the session fixture
+    ``_hugo_build`` normally ensures the build runs before any test.
+    """
+    path = BIB_PUBLIC / slug / "index.html"
+    if not path.exists():
+        pytest.skip(
+            f"Built page not found: {path}\n"
+            "Run 'hugo --environment testing --destination tests/public_test' "
+            "from the repo root, then re-run the tests."
+        )
+
+    parser = _JSONLDExtractor()
+    parser.feed(path.read_text(encoding="utf-8"))
+
+    for raw in parser.blocks:
+        try:
+            data = json.loads(raw.strip())
+        except json.JSONDecodeError:
+            continue
+        if isinstance(data, dict) and data.get("@context") == "https://schema.org":
+            return data
+
+    pytest.fail(f"No schema.org JSON-LD block found in {path}")
+
+
+# ---------------------------------------------------------------------------
+# Session-scoped Hugo build
+# ---------------------------------------------------------------------------
+
+
+@pytest.fixture(scope="session", autouse=True)
+def _hugo_build() -> None:
+    """Build the Hugo test site once per pytest session when sources have changed.
+
+    Uses ``--environment testing`` which reads ``config/testing/hugo.yaml``,
+    mounting ``tests/fixtures/bibliography/`` into the content tree and
+    writing output to ``tests/public_test/``.
+
+    Set ``PYTEST_FORCE_HUGO_BUILD=1`` to bypass the staleness check.
+    """
+    if not _needs_rebuild():
+        return
+
+    result = subprocess.run(
+        [
+            "hugo",
+            "--environment", "testing",
+            "--destination", "tests/public_test",
+        ],
+        cwd=str(REPO_ROOT),
+        capture_output=True,
+        text=True,
+    )
+    if result.returncode != 0:
+        pytest.fail(
+            f"Hugo test build failed (exit {result.returncode}):\n"
+            f"--- stdout ---\n{result.stdout}\n"
+            f"--- stderr ---\n{result.stderr}"
+        )
+    if result.stderr:
+        # Surface warnings without failing so they're visible in CI logs.
+        print(f"\n[hugo warnings]\n{result.stderr}", flush=True)
+
+
+# ---------------------------------------------------------------------------
+# Shared assertion helpers
+# ---------------------------------------------------------------------------
+
+
+def _assert_base(ld: dict, expected_type: str, expected_name: str) -> None:
+    """Assert the fields present on every single-page bibliography entry."""
+    assert ld.get("@context") == "https://schema.org", (
+        f"@context must be 'https://schema.org', got {ld.get('@context')!r}"
+    )
+    assert ld.get("@type") == expected_type, (
+        f"@type must be {expected_type!r}, got {ld.get('@type')!r}"
+    )
+    assert ld.get("name") == expected_name, (
+        f"name must be {expected_name!r}, got {ld.get('name')!r}"
+    )
+    assert ld.get("inLanguage") == "en-US", (
+        f"inLanguage must be 'en-US', got {ld.get('inLanguage')!r}"
+    )
+    assert ld.get("url", "").endswith("/"), (
+        f"url must end with '/', got {ld.get('url')!r}"
+    )
+
+
+def _assert_person(
+    person: dict,
+    expected_name: str,
+    family: str | None = None,
+    given: str | None = None,
+) -> None:
+    """Assert a Schema.org Person object."""
+    assert person.get("@type") == "Person", (
+        f"Person @type must be 'Person', got {person.get('@type')!r}"
+    )
+    assert person.get("name") == expected_name, (
+        f"Person name must be {expected_name!r}, got {person.get('name')!r}"
+    )
+    if family is not None:
+        assert person.get("familyName") == family, (
+            f"familyName must be {family!r}, got {person.get('familyName')!r}"
+        )
+    if given is not None:
+        assert person.get("givenName") == given, (
+            f"givenName must be {given!r}, got {person.get('givenName')!r}"
+        )
+
+
+def _assert_org(obj: dict, expected_name: str) -> None:
+    """Assert a Schema.org Organization object."""
+    assert obj.get("@type") == "Organization", (
+        f"Expected Organization, got @type={obj.get('@type')!r}"
+    )
+    assert obj.get("name") == expected_name, (
+        f"Organization name must be {expected_name!r}, got {obj.get('name')!r}"
+    )
+
+
+# ===========================================================================
+# Per-type test classes
+# ===========================================================================
+
+
+class TestScholarlyArticle:
+    """article-journal → ScholarlyArticle
+
+    Mock fixture: ZTEST-JOURNAL.md
+    Authors: Smith, Alice J. | Jones, Bob
+    Journal: Journal of Test Science  vol 5, issue 2, pp 45-67
+    Concepts: Interlisp, ProgrammingLanguages  (tests about[] + keywords)
+    """
+
+    def test_schema_type(self):
+        assert _load_jsonld("ztest-journal")["@type"] == "ScholarlyArticle"
+
+    def test_base_fields(self):
+        _assert_base(_load_jsonld("ztest-journal"), "ScholarlyArticle", "Test Scholarly Article")
+
+    def test_date_published(self):
+        assert _load_jsonld("ztest-journal")["datePublished"] == "2020-03-15"
+
+    def test_date_modified(self):
+        assert _load_jsonld("ztest-journal")["dateModified"] == "2023-01-10T00:00:00Z"
+
+    def test_description_from_abstract(self):
+        desc = _load_jsonld("ztest-journal").get("description", "")
+        assert "journal article" in desc.lower()
+
+    def test_authors_count_and_order(self):
+        authors = _load_jsonld("ztest-journal")["author"]
+        assert len(authors) == 2, f"Expected 2 authors, got {len(authors)}"
+        # "Smith, Alice J." → givenName=Alice J., familyName=Smith
+        _assert_person(authors[0], "Alice J. Smith", family="Smith", given="Alice J.")
+        # "Jones, Bob" → givenName=Bob, familyName=Jones
+        _assert_person(authors[1], "Bob Jones", family="Jones", given="Bob")
+
+    def test_same_as_contains_both_urls(self):
+        same_as = _load_jsonld("ztest-journal")["sameAs"]
+        assert "https://example.com/journal-article" in same_as
+        assert "https://www.zotero.org/groups/test/items/ZTESTJNL" in same_as
+
+    def test_same_as_url_source_precedes_zotero(self):
+        """url_source must appear before zotero_url in the sameAs array."""
+        same_as = _load_jsonld("ztest-journal")["sameAs"]
+        src_idx = same_as.index("https://example.com/journal-article")
+        zoo_idx = same_as.index("https://www.zotero.org/groups/test/items/ZTESTJNL")
+        assert src_idx < zoo_idx, "url_source should appear before zotero_url in sameAs"
+
+    def test_periodical_is_part_of(self):
+        is_part_of = _load_jsonld("ztest-journal")["isPartOf"]
+        assert is_part_of["@type"] == "Periodical"
+        assert is_part_of["name"] == "Journal of Test Science"
+
+    def test_volume_number(self):
+        assert _load_jsonld("ztest-journal")["volumeNumber"] == "5"
+
+    def test_issue_number(self):
+        assert _load_jsonld("ztest-journal")["issueNumber"] == "2"
+
+    def test_pagination(self):
+        assert _load_jsonld("ztest-journal")["pagination"] == "45-67"
+
+    def test_about_defined_terms(self):
+        about = _load_jsonld("ztest-journal")["about"]
+        ids = [term["@id"] for term in about]
+        assert "https://interlisp.org/concepts/#Interlisp" in ids
+        assert "https://interlisp.org/concepts/#ProgrammingLanguages" in ids
+        for term in about:
+            assert term["@type"] == "DefinedTerm"
+            assert term["inDefinedTermSet"] == "https://interlisp.org/data/cs-concepts.jsonld"
+            assert "name" in term
+
+    def test_keywords_from_concepts(self):
+        keywords = _load_jsonld("ztest-journal")["keywords"]
+        assert "Interlisp" in keywords
+        assert "Programming Languages" in keywords
+
+
+class TestMagazineArticle:
+    """article-magazine → Article
+
+    Mock fixture: ZTEST-MAGAZINE.md
+    Maps to Schema.org Article (not ScholarlyArticle).
+    Shares the same journal-style field block as article-journal.
+    """
+
+    def test_schema_type(self):
+        assert _load_jsonld("ztest-magazine")["@type"] == "Article"
+
+    def test_base_fields(self):
+        _assert_base(_load_jsonld("ztest-magazine"), "Article", "Test Magazine Article")
+
+    def test_author(self):
+        authors = _load_jsonld("ztest-magazine")["author"]
+        assert len(authors) == 1
+        _assert_person(authors[0], "Jane Doe", family="Doe", given="Jane")
+
+    def test_periodical_is_part_of(self):
+        is_part_of = _load_jsonld("ztest-magazine")["isPartOf"]
+        assert is_part_of["@type"] == "Periodical"
+        assert is_part_of["name"] == "Computing Monthly"
+
+    def test_volume_issue_pagination(self):
+        ld = _load_jsonld("ztest-magazine")
+        assert ld["volumeNumber"] == "10"
+        assert ld["issueNumber"] == "6"
+        assert ld["pagination"] == "12-14"
+
+
+class TestConferencePaper:
+    """paper-conference → ScholarlyArticle
+
+    Mock fixture: ZTEST-CONFERENCE.md
+    Uses proceedings_title (isPartOf Book), publisher, and place
+    (locationCreated Place).
+    """
+
+    def test_schema_type(self):
+        assert _load_jsonld("ztest-conference")["@type"] == "ScholarlyArticle"
+
+    def test_base_fields(self):
+        _assert_base(_load_jsonld("ztest-conference"), "ScholarlyArticle", "Test Conference Paper")
+
+    def test_proceedings_is_part_of(self):
+        is_part_of = _load_jsonld("ztest-conference")["isPartOf"]
+        assert is_part_of["@type"] == "Book"
+        assert is_part_of["name"] == "Proceedings of the Test Conference 2019"
+
+    def test_publisher(self):
+        _assert_org(_load_jsonld("ztest-conference")["publisher"], "ACM")
+
+    def test_location_created(self):
+        """place front-matter field maps to locationCreated Place."""
+        location = _load_jsonld("ztest-conference")["locationCreated"]
+        assert location["@type"] == "Place"
+        assert location["name"] == "San Francisco, CA"
+
+    def test_authors_with_compound_given_name(self):
+        """'Brown, Carol K.' splits to givenName='Carol K.', familyName='Brown'."""
+        authors = _load_jsonld("ztest-conference")["author"]
+        assert len(authors) == 2
+        _assert_person(authors[0], "Carol K. Brown", family="Brown", given="Carol K.")
+        _assert_person(authors[1], "David White", family="White", given="David")
+
+
+class TestBook:
+    """book → Book
+
+    Mock fixture: ZTEST-BOOK.md
+    """
+
+    def test_schema_type(self):
+        assert _load_jsonld("ztest-book")["@type"] == "Book"
+
+    def test_base_fields(self):
+        _assert_base(_load_jsonld("ztest-book"), "Book", "Test Book Title")
+
+    def test_publisher(self):
+        _assert_org(_load_jsonld("ztest-book")["publisher"], "Test Publisher")
+
+    def test_author(self):
+        authors = _load_jsonld("ztest-book")["author"]
+        assert len(authors) == 1
+        _assert_person(authors[0], "Test Author", family="Author", given="Test")
+
+    def test_same_as_order(self):
+        """url_source must be the first element; zotero_url must be the second."""
+        same_as = _load_jsonld("ztest-book")["sameAs"]
+        assert same_as[0] == "https://example.com/book"
+        assert same_as[1] == "https://www.zotero.org/groups/test/items/ZTESTBOOK"
+
+
+class TestChapter:
+    """chapter → Chapter
+
+    Mock fixture: ZTEST-CHAPTER.md
+    isPartOf is a Book that also carries a nested publisher Organization.
+    """
+
+    def test_schema_type(self):
+        assert _load_jsonld("ztest-chapter")["@type"] == "Chapter"
+
+    def test_is_part_of_book(self):
+        parent = _load_jsonld("ztest-chapter")["isPartOf"]
+        assert parent["@type"] == "Book"
+        assert parent["name"] == "Test Book of Chapters"
+
+    def test_parent_book_publisher(self):
+        """Publisher is nested inside the isPartOf Book object."""
+        parent = _load_jsonld("ztest-chapter")["isPartOf"]
+        _assert_org(parent["publisher"], "Chapter Publisher")
+
+    def test_pagination(self):
+        assert _load_jsonld("ztest-chapter")["pagination"] == "100-120"
+
+    def test_editor(self):
+        editors = _load_jsonld("ztest-chapter")["editor"]
+        assert len(editors) == 1
+        _assert_person(editors[0], "Test Editor", family="Editor", given="Test")
+
+    def test_author(self):
+        authors = _load_jsonld("ztest-chapter")["author"]
+        assert len(authors) == 1
+        _assert_person(authors[0], "Test Writer", family="Writer", given="Test")
+
+
+class TestReport:
+    """report → Report
+
+    Mock fixture: ZTEST-REPORT.md
+    """
+
+    def test_schema_type(self):
+        assert _load_jsonld("ztest-report")["@type"] == "Report"
+
+    def test_base_fields(self):
+        _assert_base(_load_jsonld("ztest-report"), "Report", "Test Technical Report")
+
+    def test_publisher(self):
+        _assert_org(_load_jsonld("ztest-report")["publisher"], "Test Research Lab")
+
+    def test_author(self):
+        authors = _load_jsonld("ztest-report")["author"]
+        assert len(authors) == 1
+        _assert_person(authors[0], "Test Researcher", family="Researcher", given="Test")
+
+
+class TestThesis:
+    """thesis → Thesis
+
+    Mock fixture: ZTEST-THESIS.md
+    """
+
+    def test_schema_type(self):
+        assert _load_jsonld("ztest-thesis")["@type"] == "Thesis"
+
+    def test_base_fields(self):
+        _assert_base(_load_jsonld("ztest-thesis"), "Thesis", "Test Doctoral Thesis")
+
+    def test_source_organization(self):
+        org = _load_jsonld("ztest-thesis")["sourceOrganization"]
+        assert org["@type"] == "CollegeOrUniversity"
+        assert org["name"] == "Test University"
+
+    def test_author(self):
+        authors = _load_jsonld("ztest-thesis")["author"]
+        assert len(authors) == 1
+        _assert_person(authors[0], "Test Student", family="Student", given="Test")
+
+    def test_no_publisher_key(self):
+        """Theses use sourceOrganization, not publisher."""
+        assert "publisher" not in _load_jsonld("ztest-thesis"), (
+            "Thesis should use sourceOrganization, not publisher"
+        )
+
+
+class TestPatent:
+    """patent → CreativeWork + additionalType "Patent"
+
+    Mock fixture: ZTEST-PATENT.md
+    Verifies both PropertyValue identifier objects, copyrightHolder (assignee),
+    and validIn DefinedRegion (issuing authority).
+    """
+
+    def test_schema_type_is_creative_work(self):
+        assert _load_jsonld("ztest-patent")["@type"] == "CreativeWork"
+
+    def test_additional_type_is_patent(self):
+        assert _load_jsonld("ztest-patent")["additionalType"] == "Patent"
+
+    def test_patent_number_identifier(self):
+        identifiers = _load_jsonld("ztest-patent")["identifier"]
+        match = next(
+            (i for i in identifiers if i.get("propertyID") == "patent-number"), None
+        )
+        assert match is not None, "No 'patent-number' identifier found"
+        assert match["@type"] == "PropertyValue"
+        assert match["value"] == "US9876543B2"
+
+    def test_application_number_identifier(self):
+        identifiers = _load_jsonld("ztest-patent")["identifier"]
+        match = next(
+            (i for i in identifiers if i.get("propertyID") == "application-number"), None
+        )
+        assert match is not None, "No 'application-number' identifier found"
+        assert match["@type"] == "PropertyValue"
+        assert match["value"] == "US12345678"
+
+    def test_assignee_maps_to_copyright_holder(self):
+        """Patent assignee (rights owner) maps to copyrightHolder, not funder."""
+        holder = _load_jsonld("ztest-patent")["copyrightHolder"]
+        _assert_org(holder, "Test Corporation")
+
+    def test_issuing_authority_maps_to_valid_in(self):
+        """Issuing authority (jurisdiction) maps to validIn DefinedRegion."""
+        region = _load_jsonld("ztest-patent")["validIn"]
+        assert region["@type"] == "DefinedRegion"
+        assert region["name"] == "United States"
+
+    def test_author(self):
+        authors = _load_jsonld("ztest-patent")["author"]
+        assert len(authors) == 1
+        _assert_person(authors[0], "Test Inventor", family="Inventor", given="Test")
+
+
+class TestWebPage:
+    """webpage → WebPage
+
+    Mock fixture: ZTEST-WEBPAGE.md
+    """
+
+    def test_schema_type(self):
+        assert _load_jsonld("ztest-webpage")["@type"] == "WebPage"
+
+    def test_base_fields(self):
+        _assert_base(_load_jsonld("ztest-webpage"), "WebPage", "Test Web Page")
+
+    def test_is_part_of_website(self):
+        parent = _load_jsonld("ztest-webpage")["isPartOf"]
+        assert parent["@type"] == "WebSite"
+        assert parent["name"] == "Test Website"
+
+
+class TestBlogPosting:
+    """post-weblog → BlogPosting
+
+    Mock fixture: ZTEST-BLOG.md
+    """
+
+    def test_schema_type(self):
+        assert _load_jsonld("ztest-blog")["@type"] == "BlogPosting"
+
+    def test_base_fields(self):
+        _assert_base(_load_jsonld("ztest-blog"), "BlogPosting", "Test Blog Post")
+
+    def test_is_part_of_blog(self):
+        parent = _load_jsonld("ztest-blog")["isPartOf"]
+        assert parent["@type"] == "Blog"
+        assert parent["name"] == "Test Tech Blog"
+
+
+class TestVideoObject:
+    """motion_picture → VideoObject
+
+    Mock fixture: ZTEST-VIDEO.md
+    """
+
+    def test_schema_type(self):
+        assert _load_jsonld("ztest-video")["@type"] == "VideoObject"
+
+    def test_base_fields(self):
+        _assert_base(_load_jsonld("ztest-video"), "VideoObject", "Test Motion Picture")
+
+    def test_production_company(self):
+        _assert_org(_load_jsonld("ztest-video")["productionCompany"], "Test Film Studio")
+
+    def test_encoding_format(self):
+        assert _load_jsonld("ztest-video")["encodingFormat"] == "MP4"
+
+    def test_part_of_series(self):
+        series = _load_jsonld("ztest-video")["partOfSeries"]
+        assert series["@type"] == "CreativeWorkSeries"
+        assert series["name"] == "Test Film Series"
+
+
+class TestSoftwareSourceCode:
+    """software → SoftwareSourceCode
+
+    Mock fixture: ZTEST-SOFTWARE.md
+    Also validates the single-name (no comma) author edge case via the
+    "Singularity" author entry, which has no family/given split.
+    """
+
+    def test_schema_type(self):
+        assert _load_jsonld("ztest-software")["@type"] == "SoftwareSourceCode"
+
+    def test_base_fields(self):
+        _assert_base(_load_jsonld("ztest-software"), "SoftwareSourceCode", "Test Software")
+
+    def test_two_author_objects_present(self):
+        assert len(_load_jsonld("ztest-software")["author"]) == 2
+
+    def test_author_with_comma_split(self):
+        """'Developer, Test' → givenName='Test', familyName='Developer'."""
+        authors = _load_jsonld("ztest-software")["author"]
+        _assert_person(authors[0], "Test Developer", family="Developer", given="Test")
+
+    def test_author_without_comma_has_only_name(self):
+        """'Singularity' (no comma) → only 'name' key, no familyName/givenName."""
+        authors = _load_jsonld("ztest-software")["author"]
+        single = next(
+            (a for a in authors if a["name"] == "Singularity"),
+            None,
+        )
+        assert single is not None, "'Singularity' author not found in author array"
+        assert single["@type"] == "Person"
+        assert "familyName" not in single, (
+            "A name without a comma must not produce a familyName key"
+        )
+        assert "givenName" not in single, (
+            "A name without a comma must not produce a givenName key"
+        )
+
+
+class TestEncyclopediaEntry:
+    """entry-encyclopedia → Article with isPartOf Book
+
+    Mock fixture: ZTEST-ENCYCLOPEDIA.md
+    """
+
+    def test_schema_type(self):
+        assert _load_jsonld("ztest-encyclopedia")["@type"] == "Article"
+
+    def test_base_fields(self):
+        _assert_base(_load_jsonld("ztest-encyclopedia"), "Article", "Test Encyclopedia Entry")
+
+    def test_is_part_of_book(self):
+        """encyclopedia_title maps to isPartOf Book."""
+        parent = _load_jsonld("ztest-encyclopedia")["isPartOf"]
+        assert parent["@type"] == "Book"
+        assert parent["name"] == "Encyclopedia of Test Computing"
+
+
+class TestPersonalCommunication:
+    """personal_communication → Message
+
+    Mock fixture: ZTEST-MESSAGE.md
+    """
+
+    def test_schema_type(self):
+        assert _load_jsonld("ztest-message")["@type"] == "Message"
+
+    def test_base_fields(self):
+        _assert_base(_load_jsonld("ztest-message"), "Message", "Test Personal Communication")
+
+    def test_author(self):
+        authors = _load_jsonld("ztest-message")["author"]
+        assert len(authors) == 1
+        _assert_person(authors[0], "Test Sender", family="Sender", given="Test")
+
+
+# ===========================================================================
+# Cross-cutting / edge-case tests
+# ===========================================================================
+
+
+class TestCommonFields:
+    """Shared field correctness and edge cases that span multiple types."""
+
+    def test_date_published_iso_format(self):
+        """datePublished is always YYYY-MM-DD regardless of input format."""
+        cases = [
+            ("ztest-journal", "2020-03-15"),
+            ("ztest-book", "1995-01-01"),
+            ("ztest-thesis", "2010-05-01"),
+        ]
+        for slug, expected in cases:
+            ld = _load_jsonld(slug)
+            assert ld.get("datePublished") == expected, (
+                f"{slug}: expected datePublished={expected!r}, "
+                f"got {ld.get('datePublished')!r}"
+            )
+
+    def test_date_modified_preserved_verbatim(self):
+        """dateModified is the raw lastmod string from front matter."""
+        assert _load_jsonld("ztest-report")["dateModified"] == "2023-04-01T00:00:00Z"
+
+    def test_description_from_abstract(self):
+        """The abstract front-matter field becomes the JSON-LD description."""
+        assert "test abstract for a book" in (
+            _load_jsonld("ztest-book").get("description", "").lower()
+        )
+
+    def test_in_language_always_en_us(self):
+        """Every bibliography page must carry inLanguage='en-US'."""
+        for slug in FIXTURE_SLUGS:
+            assert _load_jsonld(slug).get("inLanguage") == "en-US", (
+                f"{slug}: inLanguage must be 'en-US'"
+            )
+
+    def test_context_always_schema_org(self):
+        """Every bibliography page must declare @context='https://schema.org'."""
+        for slug in FIXTURE_SLUGS:
+            assert _load_jsonld(slug).get("@context") == "https://schema.org", (
+                f"{slug}: @context must be 'https://schema.org'"
+            )
+
+    def test_same_as_absent_when_no_urls(self):
+        """When neither url_source nor zotero_url is set, sameAs must be omitted."""
+        ld = _load_jsonld("ztest-no-urls")
+        assert "sameAs" not in ld, (
+            f"sameAs must not be present when no URLs are set, got {ld.get('sameAs')!r}"
+        )
+
+    def test_journal_keys_absent_from_non_journal_types(self):
+        """Journal-specific keys must not bleed into Book, Thesis, or Report pages."""
+        journal_keys = ("volumeNumber", "issueNumber", "pagination")
+        for slug in ("ztest-book", "ztest-thesis", "ztest-report"):
+            ld = _load_jsonld(slug)
+            for key in journal_keys:
+                assert key not in ld, (
+                    f"{slug} must not have journal key '{key}'"
+                )
+
+    def test_conference_keys_absent_from_journal(self):
+        """Conference-specific keys must not appear on journal article pages."""
+        ld = _load_jsonld("ztest-journal")
+        assert "locationCreated" not in ld, (
+            "locationCreated must not appear on journal article pages"
+        )
+
+
+class TestCollectionPage:
+    """The bibliography section page emits CollectionPage + ItemList JSON-LD."""
+
+    def test_schema_type(self):
+        ld = _load_jsonld_section()
+        assert ld["@type"] == "CollectionPage"
+
+    def test_context(self):
+        assert _load_jsonld_section()["@context"] == "https://schema.org"
+
+    def test_in_language(self):
+        assert _load_jsonld_section()["inLanguage"] == "en-US"
+
+    def test_main_entity_is_item_list(self):
+        main = _load_jsonld_section()["mainEntity"]
+        assert main["@type"] == "ItemList"
+
+    def test_item_list_contains_fixture_entries(self):
+        """The ItemList must include at least the fixture pages."""
+        items = _load_jsonld_section()["mainEntity"]["itemListElement"]
+        urls = {item["url"] for item in items}
+        # Every fixture page should appear as a list item.
+        for slug in FIXTURE_SLUGS:
+            assert any(slug in u for u in urls), (
+                f"ItemList missing entry for fixture slug '{slug}'"
+            )
+
+    def test_item_list_positions_are_sequential(self):
+        items = _load_jsonld_section()["mainEntity"]["itemListElement"]
+        positions = [item["position"] for item in items]
+        assert positions == list(range(1, len(items) + 1)), (
+            "ItemList positions must be consecutive integers starting at 1"
+        )
+
+    def test_number_of_items_matches_list_length(self):
+        main = _load_jsonld_section()["mainEntity"]
+        assert main["numberOfItems"] == len(main["itemListElement"])
+
+
+@functools.lru_cache(maxsize=1)
+def _load_jsonld_section() -> dict:
+    """Return the Schema.org JSON-LD dict from the bibliography section index page."""
+    path = TEST_PUBLIC / "history" / "bibliography" / "index.html"
+    if not path.exists():
+        pytest.skip(f"Section index not found: {path}")
+
+    parser = _JSONLDExtractor()
+    parser.feed(path.read_text(encoding="utf-8"))
+
+    for raw in parser.blocks:
+        try:
+            data = json.loads(raw.strip())
+        except json.JSONDecodeError:
+            continue
+        if isinstance(data, dict) and data.get("@type") == "CollectionPage":
+            return data
+
+    pytest.fail(f"No CollectionPage JSON-LD block found in {path}")