@misc{indiciae629b3c59fc4f,
  title = {The Mizpah coal field, Custer County, Montana},
  author = {Frank Stephens Parker and David A. Andrews},
  year = {1939},
  doi = {10.3133/b906c},
  url = {https://pubs.usgs.gov/publication/b906C},
  note = {Source identifier: b906C}
}