OF-78-09 Coal Mines and Coal Analysis of the Denver and Cheyenne Basins OF-78-09 Coal Mines and Coal Analysis of the Denver and Cheyenne Basins, Colorado
OF-77-01 Preliminary Investigation and Feasibility Study of Environmental Impact of Energy Resource Development in the Denver Basin (detail) OF-77-01 Preliminary Investigation and Feasibility Study of Environmental Impact of Energy Resource Development in the Denver Basin