@misc{234216,
  author = {Ronald Colle and Lizbeth Laureano-Perez and Svetlana Nour and Jerome LaRosa and Brian Zimmerman and Leticia Pibida and Denis Bergeron},
  title = {Natural Uranium Radioactivity Solution Standard: SRM 4321d},
  year = {2017},
  number = {122},
  month = {2017-12-27},
  publisher = {Journal of Research (NIST JRES), National Institute of Standards and Technology, Gaithersburg, MD},
  doi = {https://doi.org/10.6028/jres.122.044},
  language = {en},
}