Accretion Disc-Corona Models and X/gamma-ray Spectra of Accreting Black   Holes
  We discuss properties of thermal and hybrid (thermal/non-thermal) electron-positron plasmas in the pair and energy equilibria. Various accretion disc-corona models, recently proposed to explain properties of galactic as well as extragalactic accreting black holes, are confronted with the observed broad-band X-ray and gamma-ray spectra. 
Juri Poutanen (Stockholm Observatory)