Não informado. (1941). Conservation bulletin of the Fish Wildlife Service, United States. U.S. Fish and Wildlife Service.
Citação do estilo Chicago (17ª ed.)Não informado. Conservation Bulletin of the Fish Wildlife Service, United States. Washington: U.S. Fish and Wildlife Service, 1941.
Citação MLA (8ª ed.)Não informado. Conservation Bulletin of the Fish Wildlife Service, United States. U.S. Fish and Wildlife Service, 1941.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.