@misc{indiciae37dfc6d64642,
  title = {Central Black Hills folio, South Dakota},
  author = {Nelson Horatio Darton and Sidney Paige},
  year = {1925},
  doi = {10.3133/gf219},
  url = {https://pubs.usgs.gov/publication/gf219},
  note = {Source identifier: gf219}
}