University of Chicago Library Classics Resources Page
University of Chicago Library Catalog
Reciprocal Borrowing Program for Northwestern students and faculty at the University of Chicago, University of Illinois at Chicago, and Loyola University.
Art Institute of Chicago: Ryerson and Burnham Libraries
Worldcat contains over 95 million records from the online catalogs of libraries around the world, but particularly in North America.
Hollis Harvard's Online Catalog
Karlsruher virtueller Katalog allows cross-searching of many German and other international library catalogs.