@misc{indiciaeccf29fd13a46,
  title = {Surface water supply of the United States, 1939, Part V, Hudson Bay and upper Mississippi River basin},
  author = {Members of the Engineering Geology and Ground Water Branches, U.S. Geological Survey},
  year = {1941},
  doi = {10.3133/wsp875},
  url = {https://pubs.usgs.gov/publication/wsp875},
  note = {Source identifier: wsp875}
}