A union catalog is a “catalog of catalogs,” which lists, and, to a certain extent, bibliographically controls the holdings of a number of libraries. Why rely on a union catalog? To find and access items that may not be held at your local library.
OCLC catalog of millions of records for books, journal titles and materials in other formats from approximately 12,000 libraries worldwide.
[Coverage: 1000 A.D.-present]
SUDOC Contains some 10 million bibliographic records (books, theses, periodicals, manuscripts, a significant number of high quality images accessible online through links, and other document types). Includes library locations (look for the button "localisation" near the bottom of the results screen). Use this resource also to locate French language humanities and social sciences theses and dissertations held at member libraries. Coverage begins with 1972. For coverage of US and Canadian dissertations, see Dissertation Abstracts International [DAI/ProQuest] (remote access to DAI limited to UCD users only).
Der KVK ist eine Meta-Suchmaschine zum Nachweis von mehreren hundert Millionen Büchern, Zeitschriften und anderen Medien in Bibliotheks- und Buchhandelskatalogen weltweit. The Karlsruhe Virtual Catalog is a meta-search engine for locating hundreds of millions of books, periodicals, and other media in library and book trade catalogues throughout the world.