Evidence for metallicity spreads in three massive M 31 globular clusters I. Fuentes-Carrera, P. Jablonka, A. Sarajedini, T. Bridges, G. Djorgovski and G. Meylan A&A, 483 3 (2008) 769-781 Published online: 01 April 2008 DOI: 10.1051/0004-6361:20078899