@misc{indiciae0331507699fe,
  title = {Geologic map of the Salt Lick quadrangle, east-central Kentucky},
  author = {John Calvin Philley},
  year = {1978},
  doi = {10.3133/gq1499},
  url = {https://pubs.usgs.gov/publication/gq1499},
  note = {Source identifier: gq1499}
}