@misc{indiciaeba2e53a4cadc,
  title = {Geologic map of the Blackey quadrangle, Letcher and Knott Counties, Kentucky},
  author = {Henry A. Waldrop},
  year = {1976},
  doi = {10.3133/gq1322},
  url = {https://pubs.usgs.gov/publication/gq1322},
  note = {Source identifier: gq1322}
}