@misc{indiciaeb1f167f5bf16,
  title = {Geological and geophysical survey of fluorspar areas in Hardin County, Illinois - Part 1, Geology of the Cave in Rock district; Part 2, An exploratory study of faults in the Cave in Rock and Rosiclare districts by the earth-resistivity method},
  author = {Louis W. Currier and Oscar Emil Wagner and M. King Hubbert},
  year = {1944},
  doi = {10.3133/b942},
  url = {https://pubs.usgs.gov/publication/b942},
  note = {Source identifier: b942}
}