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+TPAC Discoverability Enhancements
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+A number of discoverability enhancements have been made to the catalog
+to better support search engines:
+
+ * Titles of catalog pages now follow a "Page title - Library name" pattern
+ to provide more specific titles in search results, bookmarks, and browser
+ tabs.
+ * The OpenSearch title now specifies the library name instead of the generic
+ "Evergreen OpenSearch" at every scope.
+ * Subject headings are now exposed as http://schema.org/about[schema:about]
+ properties instead of http://schema.org/keyword[schema:keyword].
+ * Electronic resources are now assigned a http://schema.org/url[schema:url]
+ property, and any notes or link text are assigned a
+ http://schema.org/description[schema:description] property.
+ * Given a Library of Congress relator code for 1xx and 7xx fields, we now
+ surface the URL for that relator code along with
+ the http://schema.org/contributor[schema:contributor] property to give
+ machines a better chance of understanding how the person or organization
+ actually contributed to this work.
+ * Linking out to related records:
+ ** Given an LCCN (010 field), we link to the corresponding Library of Congress
+ record using http://schema.org/sameAs[schema:sameAs].
+ ** Given an OCLC number (035 field, subfield `a` beginning with `(OCoLC)`), we
+ link to the corresponding WorldCat record using
+ http://schema.org/sameAs[schema:sameAs].
+ ** Given a URI (024 field, subfield 2 = `'uri'`), we link to the
+ corresponding OCLC Work Entity record using
+ http://schema.org/exampleOfWork[schema:exampleOfWork].
+ * The sitemap generator script now includes located URIs as well as copies
+ listed in the `asset.opac_visible_copies` materialized view, and checks
+ the children or ancestors of the requested libraries for holdings as well.
+ * Links that robots should not crawl, such as search result links, are now
+ marked with the http://www.postgresql.org/docs/9.4/static/release-9-4-1.html[@rel="nofollow"]
+ property.
+ * Catalog pages for record details and for library descriptions now express
+ a https://support.google.com/webmasters/answer/139066?hl=en[@rel="canonical"]
+ link to simplify the number of variations of page URLs that could otherwise
+ have been derived from different search parameters.
+ * Catalog pages that do not exist now return a proper 404 "HTTP_NOT_FOUND"
+ HTTP status code, and record detail pages for records that have been deleted
+ now return a proper 410 "HTTP_GONE" HTTP status code, instead of returning a
+ misleading 200 "OK" HTTP status code.