@misc{indiciae74fe04e47414,
  title = {Assessing groundwater vulnerability to agrichemical contamination in the Midwest US},
  author = {M. R. Burkart and D.W. Kolpin and D.E. James},
  year = {1999},
  doi = {10.1016/s0273-1223(99)00042-6},
  url = {https://pubs.usgs.gov/publication/70021759},
  note = {Source identifier: 70021759}
}