APA (7th ed.) Citation

United States. Bureau of Mines. (1939). Mine Safety Board decision 31: Main fan installations at metal mines. [s.n.].

Chicago Style (17th ed.) Citation

United States. Bureau of Mines. Mine Safety Board Decision 31: Main Fan Installations at Metal Mines. [Washington]: [s.n.], 1939.

MLA (9th ed.) Citation

United States. Bureau of Mines. Mine Safety Board Decision 31: Main Fan Installations at Metal Mines. [s.n.], 1939.