@misc{indiciae99d1dd2754f0,
  title = {Natural ground-water quality in Michigan, 1974-87},
  author = {T. Ray Cummings},
  year = {1989},
  doi = {10.3133/ofr89259},
  url = {https://pubs.usgs.gov/publication/ofr89259},
  note = {Source identifier: ofr89259}
}