Strong lensing efficiency of galaxy clusters in dark energy cosmologies M. Meneghetti, M. Bartelmann, K. Dolag, L. Moscardini, F. Perrotta, C. Baccigalupi and G. Tormen A&A, 442 2 (2005) 413-422 Published online: 07 October 2005 DOI: 10.1051/0004-6361:20041232