Sahih Muslim Book 4, Hadith Number 1914.

Chapter : Hadith pertaining to giving instruction in Kbutba.

Abu Huraira reported that the Apostle of Allah (may peace be upon him) used to recite in the dawn prayer on Friday: “Alif-Lam-Mim, Tanzil” in the first rak’ah, and in the second one: “Surely there came over the man a time when he was nothing that could be mentioned.”