@misc{indiciaea36f86850dc5,
  title = {Metalliferous deposits of the greater Helena mining region, Montana},
  author = {Joseph Thomas Pardee and F. C. Schrader},
  year = {1933},
  doi = {10.3133/b842},
  url = {https://pubs.usgs.gov/publication/b842},
  note = {Source identifier: b842}
}