@misc{indiciae257214e554dc,
  title = {Coal resource occurrence and coal development potential maps of the Hamilton Draw Quadrangle, Rosebud, Big Horn, and Powder River counties, Montana},
  author = {W. J. Mapel and B. K. Martin and B. A. Butler},
  year = {1978},
  doi = {10.3133/ofr7840},
  url = {https://pubs.usgs.gov/publication/ofr7840},
  note = {Source identifier: ofr7840}
}