APA (7th ed.) Citation

United States. National Park Service. (2002). Lewis and Clark Trail: National historic trail, Illinois to Oregon. National Park Service.

Chicago Style (17th ed.) Citation

United States. National Park Service. Lewis and Clark Trail: National Historic Trail, Illinois to Oregon. [Washington, D.C.]: National Park Service, 2002.

MLA (9th ed.) Citation

United States. National Park Service. Lewis and Clark Trail: National Historic Trail, Illinois to Oregon. National Park Service, 2002.