Não informado. (2001). Annual report of the United States Geological Survey. U.S. Geological Survey.
Style de citation Chicago (17e éd.)Não informado. Annual Report of the United States Geological Survey. Washington: U.S. Geological Survey, 2001.
Style de citation MLA (8e éd.)Não informado. Annual Report of the United States Geological Survey. U.S. Geological Survey, 2001.
Attention : ces citations peuvent ne pas être correctes à 100%.