@misc{indiciae273a54cb2e2d,
  title = {Natural gamma aeroradioactivity map of the Germantown and part of the Poolesville quadrangles, Montgomery and Frederick Counties, Maryland},
  author = {Jean Blanchett and Andrew Griscom and F. C. Smith},
  year = {1966},
  doi = {10.3133/gp567},
  url = {https://pubs.usgs.gov/publication/gp567},
  note = {Source identifier: gp567}
}