@misc{indiciae529b21cbd9b7,
  title = {Quality of surface waters of the United States, 1968, Parts 4 and 5, St. Lawrence River basin and Hudson Bay and upper Mississippi River basins},
  author = {Members of the Engineering Geology and Ground Water Branches, U.S. Geological Survey},
  year = {1973},
  doi = {10.3133/wsp2094},
  url = {https://pubs.usgs.gov/publication/wsp2094},
  note = {Source identifier: wsp2094}
}