Article
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY  (2005)

The unresolved hard X-ray background: the missing source population implied by the Chandra and XMM--Newton deep fields

Worsley, M. A.; Fabian, A. C.; Bauer, F. E.; Alexander, D. M.; Hasinger, G.; Mateos, S.; Brunner, H.; Brandt, W. N.; Schneider, D. P.