@misc{indiciaecd169e9969a3,
  title = {Reconnaissance for radioactivity in the Gold Hill Mining Area, Boulder County, Colorado, Part 1},
  author = {Russell H. Campbell},
  year = {1955},
  doi = {10.3133/tem563a},
  url = {https://pubs.usgs.gov/publication/tem563A},
  note = {Source identifier: tem563A}
}