TY  - RPRT
TI  - Geologic map showing thickness of the upper Cretaceous Pierre Shale in the north half of the Powder River basin, southeastern Montana and northeastern Wyoming
AU  - N.M. Denson
AU  - M.L. Gibson
AU  - G.L. Sims
PY  - 1993
DO  - 10.3133/i2380a
UR  - https://pubs.usgs.gov/publication/i2380A
ID  - i2380A
ER  -