@misc{indiciae51d71e276afe,
  title = {Long-term changes in consentrations and flux fo nitrogen in the Mississippi River Basin, USA},
  author = {D. A. Goolsby and W.A. Battaglin},
  year = {2001},
  doi = {10.1002/hyp.210},
  url = {https://pubs.usgs.gov/publication/70023286},
  note = {Source identifier: 70023286}
}