APA (7th ed.) Citation

U.S. Fish and Wildlife Service. (2009). Tundra swan Cygnus columbianus. [U.S. Fish and Wildlife Service].

Chicago Style (17th ed.) Citation

U.S. Fish and Wildlife Service. Tundra Swan Cygnus Columbianus. [Washington, D.C.]: [U.S. Fish and Wildlife Service], 2009.

MLA (9th ed.) Citation

U.S. Fish and Wildlife Service. Tundra Swan Cygnus Columbianus. [U.S. Fish and Wildlife Service], 2009.