APA (7th ed.) Citation

Ross, C. P., Andrews, D. A., & Witkind, I. J. (1955). Geologic map of Montana. Dept. of the Interior, U.S. Geological Survey.

Chicago Style (17th ed.) Citation

Ross, Clyde P., David A. Andrews, and Irving J. Witkind. Geologic Map of Montana. Washington: Dept. of the Interior, U.S. Geological Survey, 1955.

MLA (9th ed.) Citation

Ross, Clyde P., et al. Geologic Map of Montana. Dept. of the Interior, U.S. Geological Survey, 1955.