Search U.S. government technical reports digitized or harvested by TRAIL.
Analyses of Coals in the United States with Descriptions of Mine and Field Samples Collected between July 1, 1904 and June 30, 1910: Part 1. -- Analyses
Analyses of Coals in the United States with Descriptions of Mine and Field Samples Collected between July 1, 1904 and June 30, 1910 Part 2. Descriptions of Samples