@misc{indiciae57a0fe3f97d4,
  title = {Geologic map of the Center quadrangle, south-central Kentucky},
  author = {R.C. Miller and Samuel L. Moore},
  year = {1967},
  doi = {10.3133/gq693},
  url = {https://pubs.usgs.gov/publication/gq693},
  note = {Source identifier: gq693}
}