@misc{indiciaee98cdeb06201,
  title = {Geologic map of the Millersburg quadrangle, east-central Kentucky},
  author = {Norman P. Cuppels and William F. Outerbridge},
  year = {1974},
  doi = {10.3133/gq1219},
  url = {https://pubs.usgs.gov/publication/gq1219},
  note = {Source identifier: gq1219}
}