@misc{indiciae036c201d6e76,
  title = {Coal reserves of the United States - a progress report, January 1, 1960},
  author = {Paul Averitt},
  year = {1961},
  doi = {10.3133/b1136},
  url = {https://pubs.usgs.gov/publication/b1136},
  note = {Source identifier: b1136}
}