@misc{indiciaed7630ebf666e,
  title = {Proceedings of the Illinois Basin energy and mineral resources workshop},
  author = {Jennie L. Ridgley and James A. Drahovzal and B.D. Keith and Dennis R. Kolata},
  year = {1994},
  doi = {10.3133/ofr94298},
  url = {https://pubs.usgs.gov/publication/ofr94298},
  note = {Source identifier: ofr94298}
}