@misc{indiciae7d6c96235109,
  title = {The lead, zinc, and fluorspar deposits of western Kentucky},
  author = {E. O. Ulrich and W.S.T. Smith},
  year = {1905},
  doi = {10.3133/pp36},
  url = {https://pubs.usgs.gov/publication/pp36},
  note = {Source identifier: pp36}
}