@misc{indiciaed6dbf7566cd3,
  title = {The digital geologic map of Colorado in ARC/INFO format: Part A. Documentation},
  author = {Gregory N. Green},
  year = {1992},
  doi = {10.3133/ofr92507a},
  url = {https://pubs.usgs.gov/publication/ofr92507A},
  note = {Source identifier: ofr92507A}
}