Cressman, E. R., & Swanson, R. W. (1964). Stratigraphy and petrology of the Permian rocks of southwestern Montana. United States Department of the Interior, Geological Survey.
Chicago Style (17th ed.) CitationCressman, Earle Rupert, and Roger Warren Swanson. Stratigraphy and Petrology of the Permian Rocks of Southwestern Montana. Washington: United States Department of the Interior, Geological Survey, 1964.
MLA (9th ed.) CitationCressman, Earle Rupert, and Roger Warren Swanson. Stratigraphy and Petrology of the Permian Rocks of Southwestern Montana. United States Department of the Interior, Geological Survey, 1964.
Warning: These citations may not always be 100% accurate.