WorldCat is a union catalog that searches across the collections of many libraries both in the U.S. and worldwide. There is both a subscription version of the catalog from FirstSearch, as well as a freely available web version. However, WorldCat does not list the holdings of all international collections and archives, so researchers are encouraged to also explore the individual catalogs and finding aids of relevant institutions.
The Library of Congress uses standardized subject headings that can help with a search on specific topics in UC Library Search. Some examples related to Censorship are provided below. The following can also be found in individual catalog records.
Motion pictures -- Censorship -- United States
Motion pictures -- Law and legislation -- United States