APA (7th ed.) Citation

American Association of Petroleum Geologists, Geological Survey (U.S.), American Association of Petroleum Geologists. Geothermal Survey of North America Subcommittee, Schoeppel, R. J., Shelton, J. W., & Kinney, D. M. (1976). Geothermal gradient map of North America. Geological Survey.

Chicago Style (17th ed.) Citation

American Association of Petroleum Geologists, Geological Survey (U.S.), American Association of Petroleum Geologists. Geothermal Survey of North America Subcommittee, Roger J. Schoeppel, John W. Shelton, and Douglas M. Kinney. Geothermal Gradient Map of North America. Reston, Virginia: Geological Survey, 1976.

MLA (9th ed.) Citation

American Association of Petroleum Geologists, et al. Geothermal Gradient Map of North America. Geological Survey, 1976.