NUsearch is the main search tool for Northwestern University Library, combining the library catalog with a wealth of other databases and online collections.

Produced and maintained by the Transportation Research Board, TRID is the world's largest and most comprehensive bibliographic resource on transportation research information, covering all modes of transportation.

The world's most comprehensive catalog of library holdings, particularly (though not exclusively) from North American libraries, containing over 2,000,000,000 records from over 10,000 libraries.