The Physical Basis of Atomic Frequency Standards by A. S. Risley (source code)

= The Physical Basis of Atomic Frequency Standards by A. S. Risley
{c}
{tag=Work by A. S. Risley}
{title2=1971; issued April}

NBS Technical Note 399. This edition was issued in April 1971; the catalogue separately lists 1969.

https://nvlpubs.nist.gov/nistpubs/Legacy/TN/nbstechnicalnote399.pdf