GEORGE SALIBA. THE HISTORY OF AL—ṬABARÍ (TĀRĪKH AL—RUSUL WA’L—MULŪK), VOLUME XXVII, THE ABBASID REVOLUTION by JOHN ALDEN WILLIAMS;THE HISTORY OF AL—ṬABARĪ (TĀRĪKH—AL—RUSUL WA’L—MULŪK), VOL. XXXV, THE CRISIS OF THE ’ABBASID CALIPHATE - Abbasi, Muhammad Yusuf (Islamic Studies, 1987)