@misc{indiciae51ab7eb0d0d1,
  title = {The Ashland coal field, Rosebud, Powder River, and Custer Counties, Montana},
  author = {N. W. Bass},
  year = {1932},
  doi = {10.3133/b831b},
  url = {https://pubs.usgs.gov/publication/b831B},
  note = {Source identifier: b831B}
}