@misc{indiciaeb21f8697dec2,
  title = {Geologic map of the Fount Quadrangle, Knox County, Kentucky},
  author = {Russell G. Ping and R.E. Sergeant},
  year = {1977},
  doi = {10.3133/ofr77636},
  url = {https://pubs.usgs.gov/publication/ofr77636},
  note = {Source identifier: ofr77636}
}