@misc{indiciaeced0ff6cf49b,
  title = {Four newly named tongues of Eocene Green River Formation, northern Piceance Creek basin, Colorado},
  author = {Donald Cave Duncan and W. J. Hail and R. B. O'Sullivan and G. N. Pipiringos},
  year = {1974},
  doi = {10.3133/b1394f},
  url = {https://pubs.usgs.gov/publication/b1394F},
  note = {Source identifier: b1394F}
}