United States. Bureau of Mines. (1937). Mining and grinding methods and costs at Malvern Clay Co. mine, Malvern, Ohio. [s.n.].
Chicago Style (17th ed.) CitationUnited States. Bureau of Mines. Mining and Grinding Methods and Costs at Malvern Clay Co. Mine, Malvern, Ohio. [Washington]: [s.n.], 1937.
MLA (9th ed.) CitationUnited States. Bureau of Mines. Mining and Grinding Methods and Costs at Malvern Clay Co. Mine, Malvern, Ohio. [s.n.], 1937.
Warning: These citations may not always be 100% accurate.