@misc{indiciaea7c6ab5f222e,
  title = {Results of spirit leveling in Ohio, 1909 and 1910},
  author = {Robert Bradford Marshall},
  year = {1911},
  doi = {10.3133/b476},
  url = {https://pubs.usgs.gov/publication/b476},
  note = {Source identifier: b476}
}