@misc{indiciae5a20b9fee3cb,
  title = {Geophysical studies in the Yuma area, Arizona and California},
  author = {Robert E. Mattick and F. H. Olmsted and Adel A. R. Zohdy},
  year = {1973},
  doi = {10.3133/pp726d},
  url = {https://pubs.usgs.gov/publication/pp726D},
  note = {Source identifier: pp726D}
}