@misc{indiciae424892949e45,
  title = {Ancient mines in Al Kushaymiyah region, Kingdom of Saudi Arabia},
  author = {A. M. Helaby and F. C. Dodge},
  year = {1975},
  doi = {10.3133/ofr7558},
  url = {https://pubs.usgs.gov/publication/ofr7558},
  note = {Source identifier: ofr7558}
}