@misc{indiciae24eaa06dae99,
  title = {Report on the geology and resources of the Black Hills of Dakota},
  author = {Henry Newton and Walter P. Jenney and John Wesley Powell},
  year = {1880},
  doi = {10.3133/70039917},
  url = {https://pubs.usgs.gov/publication/70039917},
  note = {Source identifier: 70039917}
}