@misc{indiciaeebb197eefead,
  title = {The Christmas copper mine, Gila County, Arizona},
  author = {N. P. Peterson and R. W. Swanson},
  year = {1946},
  doi = {10.3133/ofr4622},
  url = {https://pubs.usgs.gov/publication/ofr4622},
  note = {Source identifier: ofr4622}
}