Não informado. (2000). Technical note. U.S. Department of Commerce, National Bureau of Standards.
Chicago-referens (17:e uppl.)Não informado. Technical Note. Washington: U.S. Department of Commerce, National Bureau of Standards, 2000.
MLA-referens (8:e uppl.)Não informado. Technical Note. U.S. Department of Commerce, National Bureau of Standards, 2000.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.