2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/10556The contribution of discrete sources to the gamma--ray background is modeled. Flat spectrum radio quasars are known to make a substantial contribution to the hard (E > 100 MeV) background. The so called ``MeV bump", however, cannot be accounted for in terms of known classes of sources even taking into account the newly discovered class of objects with a broad band spectrum sharply peaked in the MeV range (``MeV blazars"). Even in the most optimistic case the predicted intensity falls short of at least a factor three.4 pages, AA LaTeX, plus 3 .ps figures and style file l-aa.sty, uuencoded, gzip tar file, to appear in Astronomy and Astrophysics SupplementAstrophysicstext