Gertsch, R. E., & Bullock, R. L. (1998). Techniques in underground mining: : selections from underground mining methods handbook. Littleton, CO.: Society for Mining, Metallurgy, and Exploration.
Παραπομπή Chicago StyleGertsch, Richard E., and Richard L. Bullock. Techniques in Underground Mining: : Selections From Underground Mining Methods Handbook. Littleton, CO.: Society for Mining, Metallurgy, and Exploration, 1998.
Παραπομπή MLAGertsch, Richard E., and Richard L. Bullock. Techniques in Underground Mining: : Selections From Underground Mining Methods Handbook. Littleton, CO.: Society for Mining, Metallurgy, and Exploration, 1998.
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