@misc{indiciae3160c3ef1ec5,
  title = {Triangulation and primary traverse, 1916-1918. Primary traverse in Illinois and Wisconsin, 1916-1918},
  author = {Members of the Engineering Geology and Ground Water Branches, U.S. Geological Survey},
  year = {1923},
  doi = {10.3133/b709e},
  url = {https://pubs.usgs.gov/publication/b709E},
  note = {Source identifier: b709E}
}