Ouray National Wildlife Refuge :
plant and butterfly list /
U.S. Fish & Wildlife Service.

APA Citation

U.S. Fish and Wildlife Service. (2006). Ouray National Wildlife Refuge: plant and butterfly list. [Washington, D.C.]: U.S. Dept. of the Interior, U.S. Fish and Wildlife Service.

MLA Citation

U.S. Fish and Wildlife Service. Ouray National Wildlife Refuge: Plant And Butterfly List. [Washington, D.C.]: U.S. Dept. of the Interior, U.S. Fish and Wildlife Service, 2006.

Warning: These citations may not always be complete (especially for serials).