@misc{indiciaef1d8b69c6f3a,
  title = {Geologic map of the Valley Station quadrangle, and part of the Kosmosdale quadrangle, north-central Kentucky},
  author = {Roy Clark Kepferle},
  year = {1972},
  doi = {10.3133/gq962},
  url = {https://pubs.usgs.gov/publication/gq962},
  note = {Source identifier: gq962}
}