APA (7th ed.) Citation

Lorenz, H. W., Swenson, F. A., & Swenson, H. A. (1951). Geology and ground-water resources of the Helena Valley, Montana. United States Department of the Interior, Geological Survey.

Chicago Style (17th ed.) Citation

Lorenz, Howard Wilhelm, Frank A. Swenson, and Herbert A. Swenson. Geology and Ground-water Resources of the Helena Valley, Montana. Washington, D.C.: United States Department of the Interior, Geological Survey, 1951.

MLA (9th ed.) Citation

Lorenz, Howard Wilhelm, et al. Geology and Ground-water Resources of the Helena Valley, Montana. United States Department of the Interior, Geological Survey, 1951.