Não informado. (1971). American birds. National Audubon Society.
Style de citation Chicago (17e éd.)Não informado. American Birds. New York: National Audubon Society, 1971.
Style de citation MLA (8e éd.)Não informado. American Birds. National Audubon Society, 1971.
Attention : ces citations peuvent ne pas être correctes à 100%.