APA (7th ed.) Citation

Geological Survey (U.S.), Trent, V. A., & Spencer, F. D. (1990). Geologic map of the Anawalt quadrangle, West Virginia-Virginia. The Survey.

Chicago Style (17th ed.) Citation

Geological Survey (U.S.), Virgil A. Trent, and Frank Darwyn Spencer. Geologic Map of the Anawalt Quadrangle, West Virginia-Virginia. Reston, Va.: The Survey, 1990.

MLA (9th ed.) Citation

Geological Survey (U.S.), et al. Geologic Map of the Anawalt Quadrangle, West Virginia-Virginia. The Survey, 1990.