@misc{indiciae20c367b557f9,
  title = {Results of spirit leveling in Kansas and Nebraska, 1896 to 1909, inclusive},
  author = {Robert Bradford Marshall},
  year = {1911},
  doi = {10.3133/b473},
  url = {https://pubs.usgs.gov/publication/b473},
  note = {Source identifier: b473}
}