@misc{indiciae5e2e5f936a4a,
  title = {Geologic map of the Orangeburg quadrangle, northeastern Kentucky},
  author = {F.A. Schilling and John H. Peck},
  year = {1967},
  doi = {10.3133/gq588},
  url = {https://pubs.usgs.gov/publication/gq588},
  note = {Source identifier: gq588}
}