@misc{indiciae9a6f64d81548,
  title = {Preliminary report on Hail-Hulayfah region and progress of reconnaissance mineral survey in northeastern Hijaz quadrangle, Saudi Arabia},
  author = {C. L. Hummel and Hashim Hakim},
  year = {1972},
  doi = {10.3133/ofr72178},
  url = {https://pubs.usgs.gov/publication/ofr72178},
  note = {Source identifier: ofr72178}
}