@misc{indiciae36aad9dbe71a,
  title = {Progress report on subsurface geologic investigation in the Yuma area [Arizona]},
  author = {F. J. Frank and F. H. Olmsted},
  year = {1963},
  doi = {10.3133/ofr6334},
  url = {https://pubs.usgs.gov/publication/ofr6334},
  note = {Source identifier: ofr6334}
}