Abu Dawud
The Promised Deliverer
Book Number: 031 / Hadith Number: 4271
Narated By Umm Salamah, Ummul Mu'minin : The Prophet (pbuh) said: The Mahdi will be of my family, of the descendants of Fatimah.
Abdullah ibn Ja'far said: I heard Abu al-Malih praising Ali ibn Nufayl and describing his good qualities.