APA (7th ed.) Citation

United States. National Park Service. (1935). Zion and Bryce Canyon National Parks, Utah. U.S. G.P.O..

Chicago Style (17th ed.) Citation

United States. National Park Service. Zion and Bryce Canyon National Parks, Utah. Washington: U.S. G.P.O., 1935.

MLA (9th ed.) Citation

United States. National Park Service. Zion and Bryce Canyon National Parks, Utah. U.S. G.P.O., 1935.