Cite
MLA (8th Edition)
Geologic Map Showing Total Thickness of Coal In the North Half of the Powder River Basin, Southeastern Montana and Northeastern Wyoming. For sale by Map Distribution, The Survey, 1991.
APA (7th Edition)
Geologic map showing total thickness of coal in the north half of the Powder River Basin, southeastern Montana and northeastern Wyoming. (1991). For sale by Map Distribution, The Survey.
Chicago (17th Edition)
“Geologic Map Showing Total Thickness of Coal in the North Half of the Powder River Basin, Southeastern Montana and Northeastern Wyoming.” Denver, CO: For sale by Map Distribution, The Survey, 1991.