The XMM Deep survey in the CDF-S - I. First results on heavily obscured AGN A. Comastri, P. Ranalli, K. Iwasawa, C. Vignali, R. Gilli, I. Georgantopoulos, X. Barcons, W. N. Brandt, H. Brunner, M. Brusa et al. (18 more) A&A, 526 (2011) L9 Published online: 05 January 2011 DOI: 10.1051/0004-6361/201016119