APA (7th ed.) Citation

Paul, J. W. (1928). Questions and answers on timbering bituminous coal mines. U.S. Government Printing Office.

Chicago Style (17th ed.) Citation

Paul, J. W. Questions and Answers on Timbering Bituminous Coal Mines. [Washington?]: U.S. Government Printing Office, 1928.

MLA (9th ed.) Citation

Paul, J. W. Questions and Answers on Timbering Bituminous Coal Mines. U.S. Government Printing Office, 1928.