TY  - RPRT
TI  - Geologic map of the Powder River basin and surrounding area, Wyoming, Montana, South Dakota, North Dakota, and Nebraska
AU  - M.S. Ellis
AU  - R. B. Colton
PY  - 1994
DO  - 10.3133/i2298
UR  - https://pubs.usgs.gov/publication/i2298
ID  - i2298
ER  -