@misc{indiciae21ee4cbb5bfa,
  title = {Geology of the Denver basin in Colorado},
  author = {Samuel Franklin Emmons and Whitman Cross and George Homans Eldridge},
  year = {1896},
  doi = {10.3133/m27},
  url = {https://pubs.usgs.gov/publication/m27},
  note = {Source identifier: m27}
}