Não informado. (1941). Conservation bulletin of the Fish Wildlife Service, United States. U.S. Fish and Wildlife Service.
Chicago-viite (17. p.)Não informado. Conservation Bulletin of the Fish Wildlife Service, United States. Washington: U.S. Fish and Wildlife Service, 1941.
MLA-viite (8. p.)Não informado. Conservation Bulletin of the Fish Wildlife Service, United States. U.S. Fish and Wildlife Service, 1941.
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