TY - RPRT TI - An Assessment of gas resources in low-permeability sandstones of the Upper Cretaceous Mesaverde Group, Piceance basin, Colorado AU - R. C. Johnson AU - R. A. Crovelli AU - C. W. Spencer AU - R. F. Mast PY - 1987 DO - 10.3133/ofr87357 UR - https://pubs.usgs.gov/publication/ofr87357 ID - ofr87357 ER -