@misc{indiciae04131c7293cb,
  title = {Geologic map of the Roan Plateau area, northwestern Colorado},
  author = {W. J. Hail and R. B. O'Sullivan and M. C. Smith},
  year = {1989},
  doi = {10.3133/i1797c},
  url = {https://pubs.usgs.gov/publication/i1797C},
  note = {Source identifier: i1797C}
}