@misc{indiciaea7e9206b3359,
  title = {Geology and ore deposits of the Boulder County tungsten district, Colorado},
  author = {T. S. Lovering and Ogden Tweto},
  year = {1953},
  doi = {10.3133/pp245},
  url = {https://pubs.usgs.gov/publication/pp245},
  note = {Source identifier: pp245}
}