APA (7th ed.) Citation

United States. National Park Service. (1942). Grand Canyon National Park, Arizona. Zabel Bros..

Chicago Style (17th ed.) Citation

United States. National Park Service. Grand Canyon National Park, Arizona. Philadelphia, Pa.: Zabel Bros., 1942.

MLA (9th ed.) Citation

United States. National Park Service. Grand Canyon National Park, Arizona. Zabel Bros., 1942.

Warning: These citations may not always be 100% accurate.