@misc{indiciae92ffc1ccbc10,
  title = {Photogeologic maps of the Elk Ridge 9, 13, and 16 quadrangles, San Juan County, Utah},
  author = {Robert J. Hackman},
  year = {1952},
  doi = {10.3133/ofr5261},
  url = {https://pubs.usgs.gov/publication/ofr5261},
  note = {Source identifier: ofr5261}
}