@misc{indiciae41ac4c47fc2e,
  title = {Geology and coal reserves of the Kermit and Varney area, Kentucky},
  author = {John Warfield Huddle and Kenneth John Englund},
  year = {1966},
  doi = {10.3133/pp507},
  url = {https://pubs.usgs.gov/publication/pp507},
  note = {Source identifier: pp507}
}