Geological Survey (U.S.) & Heffern, E. L. (1993). Geologic map showing distribution of clinker in the tertiary Fort Union and Wasatch formations, northern Powder River Basin, Montana. The Survey.
Chicago Style (17th ed.) CitationGeological Survey (U.S.) and Edward L. Heffern. Geologic Map Showing Distribution of Clinker in the Tertiary Fort Union and Wasatch Formations, Northern Powder River Basin, Montana. Reston, VA: The Survey, 1993.
MLA (9th ed.) CitationGeological Survey (U.S.) and Edward L. Heffern. Geologic Map Showing Distribution of Clinker in the Tertiary Fort Union and Wasatch Formations, Northern Powder River Basin, Montana. The Survey, 1993.
Warning: These citations may not always be 100% accurate.