@misc{indiciae3b31e8e02b43,
  title = {Bedrock contours in the vicinity of Sterling, Colorado},
  author = {Paul A. Schneider and Warren E. Hofstra and Donald R. Albin},
  year = {1969},
  doi = {10.3133/ofr69241},
  url = {https://pubs.usgs.gov/publication/ofr69241},
  note = {Source identifier: ofr69241}
}