@misc{indiciaee16adbe7c13a,
  title = {Geology and water resources of a portion of the Missouri River valley in northeastern Nebraska},
  author = {George E. Condra},
  year = {1908},
  doi = {10.3133/wsp215},
  url = {https://pubs.usgs.gov/publication/wsp215},
  note = {Source identifier: wsp215}
}