APA (7e ed.) Bronvermelding

Não informado. (2001). Annual report of the United States Geological Survey. U.S. Geological Survey.

Chicago (17e ed.) Bronvermelding

Não informado. Annual Report of the United States Geological Survey. Washington: U.S. Geological Survey, 2001.

MLA (8e ed.) Bronvermelding

Não informado. Annual Report of the United States Geological Survey. U.S. Geological Survey, 2001.

Let op: Deze citaties zijn niet altijd 100% accuraat.