APA (7th ed.) Citation

Olson, J. C., Hansen, W. R., & Hedlund, D. C. (1968). Tertiary volcanic stratigraphy in the Powderhorn-Black Canyon region, Gunnison and Montrose Counties, Colorado: Nomenclature, lithology, and stratigraphic relations of a sequence of ash-flow tuffs, flows, and breccia. United States Department of the Interior, Geological Survey.

Chicago Style (17th ed.) Citation

Olson, J. C., Wallace R. Hansen, and David Carl Hedlund. Tertiary Volcanic Stratigraphy in the Powderhorn-Black Canyon Region, Gunnison and Montrose Counties, Colorado: Nomenclature, Lithology, and Stratigraphic Relations of a Sequence of Ash-flow Tuffs, Flows, and Breccia. [Washington, D.C.]: United States Department of the Interior, Geological Survey, 1968.

MLA (9th ed.) Citation

Olson, J. C., et al. Tertiary Volcanic Stratigraphy in the Powderhorn-Black Canyon Region, Gunnison and Montrose Counties, Colorado: Nomenclature, Lithology, and Stratigraphic Relations of a Sequence of Ash-flow Tuffs, Flows, and Breccia. United States Department of the Interior, Geological Survey, 1968.