Yazar
richard l unger
2 cilt bulundu.
Cilt sonuçları
Bureau of Mines research into reducing materials handling injuries
Richard L. Unger · U.S. Dept. of the Interior, Bureau of Mines
22 sayfa · 1986
Accidents / Coal mine accidents / Coal mines and mining / Mine haulage / Safety measures
Underground coal mine track inspection and cleaning vehicle
Richard L. Unger · Dept. of the Interior
34 sayfa · 1989
Coal mines and mining / Design and construction / Equipment and supplies / Mine railroads / Track maintenance vehicles