@misc{indiciae464e2f4dfd0b,
  title = {Radon in soil gas and soil radioactivity in Prince George's County, Maryland},
  author = {James K. Otton},
  year = {1992},
  doi = {10.3133/ofr9211},
  url = {https://pubs.usgs.gov/publication/ofr9211},
  note = {Source identifier: ofr9211}
}