APA (7th ed.) Citation

Geological Survey (U.S.) & Alvord, D. C. (1971). Geologic map of the Hellier quadrangle, Kentucky-Virginia and part of the Clintwood quadrangle, Pike County, Kentucky. The Survey.

Chicago Style (17th ed.) Citation

Geological Survey (U.S.) and Donald C. Alvord. Geologic Map of the Hellier Quadrangle, Kentucky-Virginia and Part of the Clintwood Quadrangle, Pike County, Kentucky. Washington, D.C.: The Survey, 1971.

MLA (9th ed.) Citation

Geological Survey (U.S.) and Donald C. Alvord. Geologic Map of the Hellier Quadrangle, Kentucky-Virginia and Part of the Clintwood Quadrangle, Pike County, Kentucky. The Survey, 1971.