@article{67016,
  author = {Thomas Parker},
  title = {Long-term comparison of caesium fountain primary frequency standards},
  year = {2009},
  number = {47},
  month = {2009-12-07},
  publisher = {Metrologia},
  url = {https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=903472},
  language = {en},
}