@misc{246211,
  author = {Kathryn Stephenson},
  title = {NIST Time and Frequency Bulletin},
  year = {2019},
  month = {2019-07-08},
  publisher = {NIST Interagency/Internal Report (NISTIR), National Institute of Standards and Technology, Gaithersburg, MD},
  doi = {https://doi.org/10.6028/NIST.IR.8261-01},
  language = {en},
}