TY  - RPRT
TI  - Mine maps of Boulder tungsten district, Colorado
AU  - Thomas Seward Lovering
AU  - Ogden L. Tweto
PY  - 1950
DO  - 10.3133/ofr5041
UR  - https://pubs.usgs.gov/publication/ofr5041
ID  - ofr5041
ER  -