@misc{1162446,
  author = {W B Mann and S B Garfinkel},
  title = {Radioactivity calibration standards:},
  year = {1970},
  month = {1970-01-01 05:01:00},
  publisher = {, National Institute of Standards and Technology, Gaithersburg, MD},
  doi = {https://doi.org/10.6028/NBS.SP.331},
  language = {en},
}