United States. National Park Service. (1992). Parkwide road improvement plan: Yellowstone National Park, Wyoming/Montana/Idaho. U.S. Dept. of the Interior, National Park Service.
Chicago Style (17th ed.) CitationUnited States. National Park Service. Parkwide Road Improvement Plan: Yellowstone National Park, Wyoming/Montana/Idaho. [Washington, D.C.?]: U.S. Dept. of the Interior, National Park Service, 1992.
MLA (9th ed.) CitationUnited States. National Park Service. Parkwide Road Improvement Plan: Yellowstone National Park, Wyoming/Montana/Idaho. U.S. Dept. of the Interior, National Park Service, 1992.
Warning: These citations may not always be 100% accurate.