prepared by Environmental Research and Technology and Berger Associates, Inc., under contract no. DE-AC01-80RA20028 ; prepared for U.S. Department of Energy, Assistant Secretary for Fossil Energy, Office of Coal Utilization and Extraction
prepared by James W. Skehan ... [and others] under contract DE-AC01-79RA20029 ; prepared for U.S. Department of Energy, Assistant Secretary for Fossil Energy, Division of Anthracite