Trumbull, J. (1957). Coal resources of Oklahoma. United States Department of the Interior, Geological Survey.
Chicago Style (17th ed.) CitationTrumbull, James. Coal Resources of Oklahoma. [Washington, D.C.]: United States Department of the Interior, Geological Survey, 1957.
MLA (9th ed.) CitationTrumbull, James. Coal Resources of Oklahoma. United States Department of the Interior, Geological Survey, 1957.
Warning: These citations may not always be 100% accurate.