Search U.S. government technical reports digitized or harvested by TRAIL.
Technology and use of lignite.Proceedings: Bureau of Mines-University of North Dakota Symposium, Grand Forks, N. Dak., April 29-30, 1965
Technology and use of lignite :proceedings, Bureau of Mines - University of North Dakota Symposium, Grand Forks, N. Dak., April 27-28, 1967