@misc{1200291,
  author = {Kathryn Stephenson},
  title = {NIST time and frequency bulletin::May},
  year = {2019},
  month = {2019-07-01 04:07:00},
  publisher = {, National Institute of Standards and Technology, Gaithersburg, MD},
  doi = {https://doi.org/10.6028/NIST.IR.8261-05},
  language = {en},
}