@misc{indiciaed773dc26dafd,
  title = {National Water-Quality Assessment Program - The Upper Mississippi River Basin},
  author = {J. R. Stark},
  year = {1994},
  doi = {10.3133/ofr94101},
  url = {https://pubs.usgs.gov/publication/ofr94101},
  note = {Source identifier: ofr94101}
}