@misc{indiciaed705ea4779f1,
  title = {COALTAB; a software program that tabulates coal resource data},
  author = {W.A. Scott and N.K. Gardner},
  year = {1987},
  doi = {10.3133/ofr8718},
  url = {https://pubs.usgs.gov/publication/ofr8718},
  note = {Source identifier: ofr8718}
}