@misc{indiciae99dbfbf32a14,
  title = {Quality of surface waters of the United States, 1967, Parts 5 and 6, Hudson Bay and Upper Mississippi River basins and Missouri River basin},
  author = {Members of the Engineering Geology and Ground Water Branches, U.S. Geological Survey},
  year = {1971},
  doi = {10.3133/wsp2013},
  url = {https://pubs.usgs.gov/publication/wsp2013},
  note = {Source identifier: wsp2013}
}