WorldCat

Over 62 million records describing books, periodicals, sound recordings, videos, musical scores, archival materials, maps, electronic resources, and much more, in over 400 different languages. Shows what materials are held by over 57,000 libraries worldwide (including most libraries in North America, and the national libraries of Australia and many Western European countries). Incorporates all records from the Research Libraries Group (RLG) Union Catalog (RLIN).

Current cumulative file. (Describes library-held materials dated from prehistory to the present.)