@misc{indiciae02d6b60ef1c4,
  title = {Geologic map of the Kirkmansville quadrangle, Muhlenberg and Todd Counties, Kentucky},
  author = {Thomas M. Kehn},
  year = {1977},
  doi = {10.3133/gq1421},
  url = {https://pubs.usgs.gov/publication/gq1421},
  note = {Source identifier: gq1421}
}