@misc{indiciae5b13317401ca,
  title = {Calloway Creek limestone and Ashlock and Drakes Formations (Upper Ordovician) in south-central Kentucky},
  author = {Gordon Whitney Weir and Robert C. Greene and George Clarke Simmons},
  year = {1965},
  doi = {10.3133/b1224d},
  url = {https://pubs.usgs.gov/publication/b1224D},
  note = {Source identifier: b1224D}
}