@misc{indiciae6e58f2ca7b5f,
  title = {U.S. Geological Survey ground-water studies in Illinois},
  author = {D. C. Voelker and J.R. Nicholas and K.L. Norton},
  year = {1988},
  doi = {10.3133/ofr88143},
  url = {https://pubs.usgs.gov/publication/ofr88143},
  note = {Source identifier: ofr88143}
}