APA (7th ed.) Citation

Geological Survey (U.S.) & DeWitt, E. (1989). Geologic map of the Black Hills area, South Dakota and Wyoming. The Survey.

Chicago Style (17th ed.) Citation

Geological Survey (U.S.) and Ed DeWitt. Geologic Map of the Black Hills Area, South Dakota and Wyoming. Reston, Va.: The Survey, 1989.

MLA (9th ed.) Citation

Geological Survey (U.S.) and Ed DeWitt. Geologic Map of the Black Hills Area, South Dakota and Wyoming. The Survey, 1989.