GALICS. II: the [ α/Fe] -mass relation in elliptical galaxies A. Pipino, J. E. G. Devriendt, D. Thomas, J. Silk and S. Kaviraj A&A, 505 3 (2009) 1075-1086 Published online: 18 August 2009 DOI: 10.1051/0004-6361/200811269