TY  - RPRT
TI  - Geologic map of parts of the Plains and Perma quadrangles, western Montana
AU  - Earle Rupert Cressman
PY  - 1981
DO  - 10.3133/ofr81785
UR  - https://pubs.usgs.gov/publication/ofr81785
ID  - ofr81785
ER  -