Kisah khalifah rasulullah - Muhd. Nur Imam (Kuala Lumpur : Darul Nu'man, 1992)
j.1 - Saiyidina Abu Bakar As-Siddiq r.a.; j.2 - Saiyidina Umar Ibnul Khattab r.a.; j.3 - Saiyidina Utsman bin Affan r.a.; j.4 - Saiyidina Ali bin Abi Thalib r.a
Keywords: Caliphate; Islamic Empire -- History