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Washington, D.C. (810 7th St., N.W., MS#9800, Washington 20241-0001) : U.S. Dept. of the Interior, Bureau of Mines, [1992]
TN23 .U43 TN312 |
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Pittsburgh, Pa. : U.S. Dept. of the Interior, Bureau of Mines, 1982.
TN312 .C6 |
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