@misc{indiciae2019dda3281a,
  title = {Geologic map of the Crested Butte quadrangle, Gunnison County, Colorado},
  author = {David L. Gaskill and Steven M. Colman and DeLong and Charles H. Robinson},
  year = {1986},
  doi = {10.3133/gq1580},
  url = {https://pubs.usgs.gov/publication/gq1580},
  note = {Source identifier: gq1580}
}