APA (7th ed.) Citation

Gordon, M., & Yochelson, E. L. (1975). Gastropoda, Cephalopoda, and Trilobita of the Amsden Formation (Mississippian and Pennsylvanian) of Wyoming. United States Department of the Interior, Geological Survey.

Chicago Style (17th ed.) Citation

Gordon, Mackenzie, and Ellis L. Yochelson. Gastropoda, Cephalopoda, and Trilobita of the Amsden Formation (Mississippian and Pennsylvanian) of Wyoming. Washington: United States Department of the Interior, Geological Survey, 1975.

MLA (9th ed.) Citation

Gordon, Mackenzie, and Ellis L. Yochelson. Gastropoda, Cephalopoda, and Trilobita of the Amsden Formation (Mississippian and Pennsylvanian) of Wyoming. United States Department of the Interior, Geological Survey, 1975.