From sundials to atomic clocks : understanding time and frequency /
Jespersen, James.
Fitz-Randolph, Jane.
Robb, John.
Miner, Dar.
Washington, D.C. : U.S. Dept. of Commerce, Technology Administration, National Institute of Standards and Technology,
1999.
"March 1999."
Includes bibliographical references (p. 300) and index.
Time.
Time measurements.
Clocks and watches.