Não informado. (2001). Statistical digest. U.S. Fish and Wildlife Service.
Style de citation Chicago (17e éd.)Não informado. Statistical Digest. Washington: U.S. Fish and Wildlife Service, 2001.
Style de citation MLA (8e éd.)Não informado. Statistical Digest. U.S. Fish and Wildlife Service, 2001.
Attention : ces citations peuvent ne pas être correctes à 100%.