@misc{indiciae0fb5e6382516,
  title = {Geologic map of the Four Corners quadrangle, Wyoming and South Dakota},
  author = {J. A. Van Lieu},
  year = {1969},
  doi = {10.3133/i581},
  url = {https://pubs.usgs.gov/publication/i581},
  note = {Source identifier: i581}
}