@misc{indiciae1f00dd9557d5,
  title = {Preliminary geologic map of the Sentinel Peak NW quadrangle, Montezuma County, Colorado},
  author = {E. B. Ekren and F. N. Houser},
  year = {1956},
  doi = {10.3133/tem889},
  url = {https://pubs.usgs.gov/publication/tem889},
  note = {Source identifier: tem889}
}