APA (7th ed.) Citation

Geological Survey & Simpson, R. W. (1987). Digital colored Bouguer gravity, free-air gravity, station location, and terrain maps for the conterminous United States. The Survey ; For sale by Map Distribution.

Chicago Style (17th ed.) Citation

Geological Survey and Robert W. Simpson. Digital Colored Bouguer Gravity, Free-air Gravity, Station Location, and Terrain Maps for the Conterminous United States. Reston, Va. : Denver, CO: The Survey ; For sale by Map Distribution, 1987.

MLA (8th ed.) Citation

Geological Survey and Robert W. Simpson. Digital Colored Bouguer Gravity, Free-air Gravity, Station Location, and Terrain Maps for the Conterminous United States. The Survey ; For sale by Map Distribution, 1987.