Parker, T.
(1999),
Performance of a Hydrogen Maser Ensemble and Characterization of Frequency Standards, IEEE Trans. Ultrason. Ferroelec. Freq. Cont., Besan{c-cedilla}on, FR, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=105535
(Accessed December 10, 2024)