MPE CONFERENCE (1991 <br/><br/>
"X-ray emission from active galactic nuclei and the cosmic x-ray background. Proceedings of a conference held at Max Planck institut fur extraterrestrische Physik,Garching,November 4-8, 1991" 

 - Germany  Max Planck Institut  1992 
 - Pbk.ix p. + 420 
 - MPE REPORT 235 .