@misc{indiciaefe1b203fa085,
  title = {Preliminary geologic map of the Erie quadrangle, Boulder, Weld, and Adams counties, Colorado},
  author = {R. B. Colton and L. W. Anderson},
  year = {1977},
  doi = {10.3133/mf882},
  url = {https://pubs.usgs.gov/publication/mf882},
  note = {Source identifier: mf882}
}