International System of Units Bibliography of links, citations and online publications of the SI, the modern
metric system of measurement, a language universally used in science. http://www.physics.nist.gov/cuu/Units/bibliography.html
NIST: Time and Frequency Division - Division 847 The National Institute of Standards and Technology maintains time and frequency
standards for the United States. http://www.twinsun.com/tz/tz-link.htm