@misc{indiciae186a8615e88e,
  title = {Geologic map of parts of the Alton and Derby quadrangles, Meade and Breckinridge Counties, Kentucky},
  author = {Dewey Harold Amos},
  year = {1970},
  doi = {10.3133/gq845},
  url = {https://pubs.usgs.gov/publication/gq845},
  note = {Source identifier: gq845}
}