APA (7th ed.) Citation

Geological Survey (U.S.), McDowell, R. C., & Milton, D. J. (1992). Geologic map of the Round Hill quadrangle, Clarke and Loudoun counties, Virginia, and Jefferson County, West Virginia. The Survey.

Chicago Style (17th ed.) Citation

Geological Survey (U.S.), Robert C. McDowell, and Daniel J. Milton. Geologic Map of the Round Hill Quadrangle, Clarke and Loudoun Counties, Virginia, and Jefferson County, West Virginia. Reston, Va.: The Survey, 1992.

MLA (9th ed.) Citation

Geological Survey (U.S.), et al. Geologic Map of the Round Hill Quadrangle, Clarke and Loudoun Counties, Virginia, and Jefferson County, West Virginia. The Survey, 1992.