Fabbiano, G. (Harvard-Smithsonian Center for Astrophysics Cambridge, MA, United States)
Klein, U. (Bonn, Universitaet Germany)
Trinchieri, G. (Harvard-Smithsonian Center for Astrophysics, Cambridge, MA; Arcetri, Osservatorio Astrofisico Florence, Italy)
Wielebinski, R. (Max-Planck-Institut fuer Radioastronomie Bonn, Germany)