Extremely massive young clusters in NGC 1365 E. Galliano, D. Alloin, E. Pantin, G. L. Granato, P. Delva, L. Silva, P. O. Lagage and P. Panuzzo A&A, 492 1 (2008) 3-22 Published online: 11 September 2008 DOI: 10.1051/0004-6361:20077621