@misc{indiciae3395be31656c,
  title = {Geologic map of the Leatherwood quadrangle, southeastern Kentucky},
  author = {Harold J. Prostka and Victor M. Seiders},
  year = {1968},
  doi = {10.3133/gq723},
  url = {https://pubs.usgs.gov/publication/gq723},
  note = {Source identifier: gq723}
}