United States. Bureau of Mines. (1984). Nonfuel mineral model directory. U.S. Dept. of the Interior, Bureau of Mines.
Chicago-viite (17. p.)United States. Bureau of Mines. Nonfuel Mineral Model Directory. [Avondale, Md.]: U.S. Dept. of the Interior, Bureau of Mines, 1984.
MLA-viite (9. p.)United States. Bureau of Mines. Nonfuel Mineral Model Directory. U.S. Dept. of the Interior, Bureau of Mines, 1984.
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