P.J. Mohr, B.N. Taylor, and D.B. Newell (2011), "The 2010 CODATA Recommended Values of the Fundamental Physical Constants" (Web Version 6.0). http://physics.nist.gov/constants. National Institute of Standards and Technology, Gaithersburg, MD 20899. Lenkje til R∞, Lenkje til hcR∞
