@misc{indiciaeb7fcae5bfd4e,
  title = {The geologic story of the Aspen region - Mines, glaciers and rocks},
  author = {Bruce Bryant and Peter L. Martin},
  year = {1988},
  doi = {10.3133/b1603},
  url = {https://pubs.usgs.gov/publication/b1603},
  note = {Source identifier: b1603}
}