TY  - RPRT
TI  - Early Proterozoic volcanogenic sequences in central Colorado: Colorado Scientific Society fall field trip, September 6-8, 1991
AU  - John Calvin Reed
AU  - Kenneth Lee Shropshire
PY  - 1991
DO  - 10.3133/ofr91431
UR  - https://pubs.usgs.gov/publication/ofr91431
ID  - ofr91431
ER  -