@misc{indiciae6722838c74a0,
  title = {Geologic map of the La Center Quadrangle, Ballard and McCracken counties, Kentucky},
  author = {Roger Warren Swanson},
  year = {1978},
  doi = {10.3133/ofr78134},
  url = {https://pubs.usgs.gov/publication/ofr78134},
  note = {Source identifier: ofr78134}
}