APA (7th ed.) Citation

Geological Survey (U.S.) & Luedke, R. G. (1996). Geologic map of the Ophir quadrangle, San Juan, San Miguel, and Dolores counties, Colorado. The Survey.

Chicago Style (17th ed.) Citation

Geological Survey (U.S.) and Robert G. Luedke. Geologic Map of the Ophir Quadrangle, San Juan, San Miguel, and Dolores Counties, Colorado. Reston, VA: The Survey, 1996.

MLA (9th ed.) Citation

Geological Survey (U.S.) and Robert G. Luedke. Geologic Map of the Ophir Quadrangle, San Juan, San Miguel, and Dolores Counties, Colorado. The Survey, 1996.