APA (7th ed.) Citation

Gregory, H. E. (1950). Geology and geography of the Zion Park region, Utah and Arizona. United States Department of the Interior, Geological Survey.

Chicago Style (17th ed.) Citation

Gregory, Herbert E. Geology and Geography of the Zion Park Region, Utah and Arizona. Washington: United States Department of the Interior, Geological Survey, 1950.

MLA (9th ed.) Citation

Gregory, Herbert E. Geology and Geography of the Zion Park Region, Utah and Arizona. United States Department of the Interior, Geological Survey, 1950.