1. We do not consider the neutrinos here as even the nature of their mass term is, as yet, uncertain. Were they to be purely Dirac ones, the hierarchy worsens.
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3. C Amsler et al, Review of Particle Physics Particle Data Group, http://pdg.lbl.gov/
4. The Tevatron Electroweak Working Group, arXiv:0903.2503
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