APA (7th ed.) Citation

Bownocker, J. A., & Clark, F. R. (1917). The coal fields of Ohio. U.S. G.P.O..

Chicago Style (17th ed.) Citation

Bownocker, J. A., and Frank Rinker Clark. The Coal Fields of Ohio. Washington: U.S. G.P.O., 1917.

MLA (9th ed.) Citation

Bownocker, J. A., and Frank Rinker Clark. The Coal Fields of Ohio. U.S. G.P.O., 1917.