from the 2007 Review of Particle Physics.
PDG citation: W.-M. Yao et al., J. Phys. G 33, 1 (2006) and 2007 partial update for the 2008 edition(bibtex)
PDG citation: W.-M. Yao et al., J. Phys. G 33, 1 (2006) and 2007 partial update for the 2008 edition(bibtex)