@misc{indiciaeeb571f39135e,
  title = {Maps showing metallic mineral districts and mines in the Black Hills, South Dakota and Wyoming},
  author = {A.B. Wilson and Ed DeWitt},
  year = {1995},
  doi = {10.3133/i2445},
  url = {https://pubs.usgs.gov/publication/i2445},
  note = {Source identifier: i2445}
}