APA (7th ed.) Citation

McIntosh, W. L., & Eister, M. F. (1981). Geologic map index of Pennsylvania. Dept. of the Interior, United States Geological Survey.

Chicago Style (17th ed.) Citation

McIntosh, Willard L., and Margaret F. Eister. Geologic Map Index of Pennsylvania. [Reston, Va.]: Dept. of the Interior, United States Geological Survey, 1981.

MLA (9th ed.) Citation

McIntosh, Willard L., and Margaret F. Eister. Geologic Map Index of Pennsylvania. Dept. of the Interior, United States Geological Survey, 1981.