@misc{indiciae08403adcddbc,
  title = {Geologic map of the Hygiene quadrangle, Boulder County, Colorado},
  author = {Richard F. Madole and William A. Braddock and Roger B. Colton},
  year = {1998},
  doi = {10.3133/gq1772},
  url = {https://pubs.usgs.gov/publication/gq1772},
  note = {Source identifier: gq1772}
}