United States. Bureau of Mines & Busch, R. A. (1975). Physical property data on fine coal refuse. U.S. Dept. of the Interior, Bureau of Mines.
Chicago-viite (17. p.)United States. Bureau of Mines ja R. A. Busch. Physical Property Data on Fine Coal Refuse. [Washington]: U.S. Dept. of the Interior, Bureau of Mines, 1975.
MLA-viite (9. p.)United States. Bureau of Mines ja R. A. Busch. Physical Property Data on Fine Coal Refuse. U.S. Dept. of the Interior, Bureau of Mines, 1975.
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