@misc{indiciae73019fd4fcc7,
  title = {Use of isotopes to identify sources of ground water, estimate ground-water-flow rates, and assess aquifer vulnerability in the Calumet region of northwestern Indiana and northeastern Illinois},
  author = {Robert T. Kay and E. Randall Bayless and Robert A. Solak},
  year = {2002},
  doi = {10.3133/wri024213},
  url = {https://pubs.usgs.gov/publication/wri024213},
  note = {Source identifier: wri024213}
}