@misc{indiciaebc34afa1c114,
  title = {Geologic radon potential of EPA Region 5; Illinois, Indiana, Michigan, Minnesota, Ohio, and Wisconsin},
  year = {1993},
  doi = {10.3133/ofr93292e},
  url = {https://pubs.usgs.gov/publication/ofr93292E},
  note = {Source identifier: ofr93292E}
}