@misc{indiciaebdfc5b7ea377,
  title = {Geologic map of the Helton quadrangle, southeastern Kentucky},
  author = {Dudley D. Rice},
  year = {1975},
  doi = {10.3133/gq1227},
  url = {https://pubs.usgs.gov/publication/gq1227},
  note = {Source identifier: gq1227}
}