@misc{indiciaefb444fb729f6,
  title = {A preliminary geologic map of the Rochford district, Black Hills, South Dakota},
  author = {R. V. McGehee and R. W. Bayley},
  year = {1969},
  doi = {10.3133/ofr69155},
  url = {https://pubs.usgs.gov/publication/ofr69155},
  note = {Source identifier: ofr69155}
}