1. U. S. Congress. Senate. Committee on Manufacturers, Hearings on S. Res. 178. Investigation of Conditions in the Coal Fields of Harlan ana Bell Counties. Kentucky, 72nd Cong., 1st sess. Washington Printing Office.
2. Morris, Homer L. 1934.The Plight of the Bituminous Coal Miner21Philadelphia
3. McDonald, David J. and Lynch, Edward A. 1939.Coal and Unionism136Maryland
4. Ross, Malcolm. 1933.Machine Age in the Hills51New York