Grand Ayatollah Saafi Golpayegani has collected all these traditions in his book: Muntakhab Al-Asar, collection of Sunni and Shia traditions and narrations. Following is the list of the subject and the number of traditions on that particular subject:
91 Hadith on: "The Imams are twelve in number, among whom the first is Ali ibn Abi Talib (as)and the last is the Mahdi(as)."
94 Hadith on: "The Imams are twelve, and the last one is the Mahdi(as)."
107 Hadith on: "The Imams are twelve, nine among whom are the descendants of Husain(as), and the ninth is the Al-Qa'im(as)."
389 Hadith on: "Mahdi(as) is from among the progeny of the Prophet(pbuh)."
214 Hadith on: "Mahdi(as) is from among the descendants of Ali(as)."
192 Hadith on: "Mahdi(as) is from among the descendants of Fatima(sa)."
185 Hadith on: "Mahdi(as) is from among the descendants of Husain(as)."