@misc{indiciaee18b33089365,
  title = {Geologic map of the North Mamm Peak quadrangle, Garfield County, Colorado},
  author = {John R. Donnell and Warren E. Yeend},
  year = {1968},
  doi = {10.3133/ofr6880},
  url = {https://pubs.usgs.gov/publication/ofr6880},
  note = {Source identifier: ofr6880}
}