APA (7th ed.) Citation

Simpson, H. E. (1960). Geology of the Yankton area, South Dakota and Nebraska. U.S. Govt. Print. Off.

Chicago Style (17th ed.) Citation

Simpson, Howard Edwin. Geology of the Yankton Area, South Dakota and Nebraska. Washington: U.S. Govt. Print. Off, 1960.

MLA (9th ed.) Citation

Simpson, Howard Edwin. Geology of the Yankton Area, South Dakota and Nebraska. U.S. Govt. Print. Off, 1960.