Most microformat materials are cataloged and can be found by searching the Main Catalog. Some large sets, however, do not have item-level cataloging, so that in order to identify individual works, users must consult a guide or index. These reference aids are located in the Microforms Service reading room, along with a small collection of text-based CDs. Call numbers for the guides and indexes have the location Film B, followed by a call number.
Microform call numbers are preceded by the descriptors MICROFILM, MICROFICHE, MICROCARD, and MICROPRINT.