@misc{indiciaec37a68da399f,
  title = {Geologic map of the Bangor quadrangle, east-central Kentucky},
  author = {David Kent Hylbert and John Calvin Philley},
  year = {1971},
  doi = {10.3133/gq947},
  url = {https://pubs.usgs.gov/publication/gq947},
  note = {Source identifier: gq947}
}