@misc{indiciae021a92ff9473,
  title = {Geology of uranium in the Chadron area, Nebraska and South Dakota},
  author = {Robert Jacob Dunham},
  year = {1961},
  doi = {10.3133/ofr6142},
  url = {https://pubs.usgs.gov/publication/ofr6142},
  note = {Source identifier: ofr6142}
}