@misc{indiciae33928e04afa7,
  title = {Geologic map of the Glasgow 1° x 30' quadrangle, Valley and McCone counties, Montana},
  author = {Roger B. Colton and Steven T. Whitaker and William C. Ehler},
  year = {1989},
  doi = {10.3133/ofr89171},
  url = {https://pubs.usgs.gov/publication/ofr89171},
  note = {Source identifier: ofr89171}
}