@misc{indiciaea75195a7e6dd,
  title = {Geology of the Boulder district, Colorado},
  author = {Nevin Melancthon Fenneman},
  year = {1905},
  doi = {10.3133/b265},
  url = {https://pubs.usgs.gov/publication/b265},
  note = {Source identifier: b265}
}