@misc{indiciae119bb0dc55f5,
  title = {Geologic map of the Craig 1 x 2 Quadrangle, northwestern Colorado},
  author = {Ogden Tweto},
  year = {1976},
  doi = {10.3133/i972},
  url = {https://pubs.usgs.gov/publication/i972},
  note = {Source identifier: i972}
}