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K.A. Olive et al. (Particle Data Group) (2016): Particle listings – π± http://pdg.lbl.gov/2016/listings/rpp2016-list-pi-plus-minus.pdf
K.A. Olive et al. (Particle Data Group) (2016): Particle listings – ρ http://pdg.lbl.gov/2016/listings/rpp2016-list-rho-770.pdf