TY - RPRT TI - Summary of the geology, mineral resources, landscape geochemistry, and engineering geologic characteristics of the northern Powder River coal region, Montana: Landscape geochemistry AU - J. J. Connor PY - 1977 DO - 10.3133/ofr77292b UR - https://pubs.usgs.gov/publication/ofr77292B ID - ofr77292B ER -