Costamante, LuigiLuigiCostamanteGHISELLINI, GabrieleGabrieleGHISELLINIWOLTER, AnnaAnnaWOLTERTAGLIAFERRI, GianpieroGianpieroTAGLIAFERRIFossati, G.G.FossatiPadovani, P.P.PadovaniGiommi, P.P.Giommi2024-02-222024-02-2220011-58381-059-51050-3390http://hdl.handle.net/20.500.12386/34813We present the main results of seven BeppoSAX observations performed with the aim to find and study more objects with "extreme" synchrotron peak frequencies.STAMPAenConference paperhttps://ui.adsabs.harvard.edu/#abs/2001ASPC..227..135Chttp://aspbooks.org/a/volumes/article_details/?paper_id=21657FIS/05 - ASTRONOMIA E ASTROFISICA