Jefferts, S.
, Meekhof, D.
, Shirley, J.
and Parker, T.
(1999),
Preliminary Accuracy Evaluation of a Cesium Fountain Primary Frequency Standard at NIST, 13^uth^ European Frequency and Time Forum and 1999 IEEE Int. Freq. Symp. , Besan{c-cedilla}on, FR, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=105321
(Accessed September 18, 2024)