@misc{indiciae3fb743c290c7,
  title = {Geology and fluorspar deposits, Northgate district, Colorado},
  author = {Thomas A. Steven},
  year = {1960},
  doi = {10.3133/b1082f},
  url = {https://pubs.usgs.gov/publication/b1082F},
  note = {Source identifier: b1082F}
}