@misc{indiciae99f8d301b505,
  title = {Structure, coal thickness, and overburden thickness of the Wall Coal Resource Unit, west half of the Birney 30' x 60' Quadrangle, Big Horn and Rosebud counties, Montana},
  author = {William C. Culbertson and Herb I. Saperstone},
  year = {1987},
  doi = {10.3133/coal111},
  url = {https://pubs.usgs.gov/publication/coal111},
  note = {Source identifier: coal111}
}