Search U.S. government technical reports digitized or harvested by TRAIL.
Coal-mine fatalities in the United States, 1922
Production of explosives in the United States :during the calendar year 1927
Falls of roof in bituminous coal mines :influence of the seasons and rate of production
Production of explosives in the United States during the calendar year 1930
Falls of roof and coal in mines operating in the Sewickley coal bed in Monongalia County, W. Va.
Production of explosives in the United States :during the calendar year 1931
Falls of roof in mines operating in the Pittsburgh Coal Bed, West Virginia