APA (7th ed.) Citation

Sasscer, R. S. (1992). U.S. Geological Survey Library classification system. United States Government Printing Office.

Chicago Style (17th ed.) Citation

Sasscer, R. Scott. U.S. Geological Survey Library Classification System. [Washington, D.C.]: United States Government Printing Office, 1992.

MLA (9th ed.) Citation

Sasscer, R. Scott. U.S. Geological Survey Library Classification System. United States Government Printing Office, 1992.