@misc{indiciae7c039873eeb3,
  title = {Geologic radon potential of EPA Region 7: Iowa, Kansas, Missouri, and Nebraska},
  year = {1993},
  doi = {10.3133/ofr93292g},
  url = {https://pubs.usgs.gov/publication/ofr93292G},
  note = {Source identifier: ofr93292G}
}