@misc{indiciaed10c8ea5fd56,
  title = {Geologic map of the outcrop area of the Hornbrook Formation, Oregon and California},
  author = {Tor Helge Nilsen and G.M. Barats and M.A. Elliott and D. L. Jones},
  year = {1983},
  doi = {10.3133/ofr83373},
  url = {https://pubs.usgs.gov/publication/ofr83373},
  note = {Source identifier: ofr83373}
}