@misc{indiciae1f8678495c66,
  title = {Geologic map of the Denver 1 degree by 2 degrees Quadrangle, north-central Colorado},
  author = {Bruce Bryant and L.W. McGrew and R. A. Wobus},
  year = {1981},
  doi = {10.3133/i1163},
  url = {https://pubs.usgs.gov/publication/i1163},
  note = {Source identifier: i1163}
}