Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

The physical basis of atomic frequency standards:



A S Risley
- NBS TN 399
Report Number
NBS TN 399


Risley, A. (1969), The physical basis of atomic frequency standards:, , National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed April 14, 2024)
Created January 1, 1969, Updated May 19, 2023