@misc{indiciae5bca3eaaae16,
  title = {Photogeologic and reconnaissance geologic map of the Knowlton Quadrangle, Custer County, Montana},
  author = {S. J. Luft and R. B. Colton and E.L. Heffern},
  year = {1984},
  doi = {10.3133/mf1697},
  url = {https://pubs.usgs.gov/publication/mf1697},
  note = {Source identifier: mf1697}
}