@misc{indiciae5349dfb75b70,
  title = {Results of spirit leveling in Pennsylvania for the years 1899 to 1905, inclusive},
  author = {Samuel Stinson Gannett and David Henry Baldwin},
  year = {1906},
  doi = {10.3133/b288},
  url = {https://pubs.usgs.gov/publication/b288},
  note = {Source identifier: b288}
}