The space density of Compton-thick AGN at z ≈ 0.8 in the zCOSMOS-Bright Survey C. Vignali, M. Mignoli, R. Gilli, A. Comastri, K. Iwasawa, G. Zamorani, V. Mainieri and A. Bongiorno A&A, 571 (2014) A34 Published online: 04 November 2014 DOI: 10.1051/0004-6361/201424791