Non-gray rotating stellar models and the evolutionary history of the Orion Nebular Cluster N. R. Landin, P. Ventura, F. D'Antona, L. T. S. Mendes and L. P. R. Vaz A&A, 456 1 (2006) 269-282 Published online: 23 August 2006 DOI: 10.1051/0004-6361:20054011