@misc{indiciae3811cd959aef,
  title = {Geology and water resources of the San Luis Valley, Colorado},
  author = {Claude Ellsworth Siebenthal},
  year = {1910},
  doi = {10.3133/wsp240},
  url = {https://pubs.usgs.gov/publication/wsp240},
  note = {Source identifier: wsp240}
}