Avogadro constant

[Etymology: L. R. A. C. Avogadro; Italy 1776-1856] fundamental constant. Symbol N_A, L. From Avogadro's number = 6.022 141 5(10) × 10²³ mol^-1 with relative standard uncertainty 1.7 × 10^-7 (i.e. 602.~ per zeptomole).
[Mohr P. J., Taylor B. N. CODATA Recommended Values of the Fundamental Physical Constants: 2002 (to be published)]
[Mohr P. J., Taylor B. N. Rev. Mod. Phys. Vol. 72:351-495 (2000)]
[Mohr P. Phys. Today Vol. 53:7, 11-16 (2000)]
[For latest recommended values, see http://physics.nist.gov/cuu/Constants/index.html]