@misc{indiciae7954baec8366,
  title = {Geologic map of the Bear Trap Creek quadrangle, Madison County, Montana},
  author = {Karl S. Kellogg},
  year = {1995},
  doi = {10.3133/gq1757},
  url = {https://pubs.usgs.gov/publication/gq1757},
  note = {Source identifier: gq1757}
}