@misc{indiciae5a61ffd4290a,
  title = {Index maps for large-scale vertical black and white aerial photographs along the Elsinore, San Jacinto, and Imperial faults, California},
  author = {Charles W. Hedel},
  year = {1979},
  doi = {10.3133/ofr79285},
  url = {https://pubs.usgs.gov/publication/ofr79285},
  note = {Source identifier: ofr79285}
}