Hackett, T. D.
Multislice mining for thick western coal seams / by T.D. Hackett, D.L. Boreck, and D.R. Clarke. - PGH [i.e. Pittsburgh] Pa. : U.S. Dept. of the Interior, Bureau of Mines, 1989. - ii, 27 p. ; ill. - Information circular . - Information circular (United States. Bureau of Mines) .
89600119
Coal mines and mining--West (U.S.)
Multislice mining for thick western coal seams / by T.D. Hackett, D.L. Boreck, and D.R. Clarke. - PGH [i.e. Pittsburgh] Pa. : U.S. Dept. of the Interior, Bureau of Mines, 1989. - ii, 27 p. ; ill. - Information circular . - Information circular (United States. Bureau of Mines) .
89600119
Coal mines and mining--West (U.S.)