Obscured and powerful AGN and starburst activities at z ~ 3.5 M. Polletta, A. Omont, S. Berta, J. Bergeron, C. S. Stalin, P. Petitjean, M. Giorgetti, G. Trinchieri, R. Srianand, H. J. McCracken et al. (2 more) A&A, 492 1 (2008) 81-92 Published online: 15 October 2008 DOI: 10.1051/0004-6361:200810345