APA (7th ed.) Citation

Geological Survey (U.S.), Thompson, R. A., & Machette, M. N. (1989). Geologic map of the San Luis Hills area, Conejos and Costilla counties, Colorado. The Survey.

Chicago Style (17th ed.) Citation

Geological Survey (U.S.), Ren A. Thompson, and Michael N. Machette. Geologic Map of the San Luis Hills Area, Conejos and Costilla Counties, Colorado. Reston, Va.: The Survey, 1989.

MLA (9th ed.) Citation

Geological Survey (U.S.), et al. Geologic Map of the San Luis Hills Area, Conejos and Costilla Counties, Colorado. The Survey, 1989.