Alvord, D. C. (1965). Geologic map of the Broad Bottom quadrangle, eastern Kentucky. U.S. Geological Survey.
Chicago Style (17th ed.) CitationAlvord, Donald C. Geologic Map of the Broad Bottom Quadrangle, Eastern Kentucky. Washington, D.C.: U.S. Geological Survey, 1965.
MLA (9th ed.) CitationAlvord, Donald C. Geologic Map of the Broad Bottom Quadrangle, Eastern Kentucky. U.S. Geological Survey, 1965.
Warning: These citations may not always be 100% accurate.