Sahih Bukhari Volume 002, Book 019, Hadith Number 174.

Narated By Abu Huraira : On Fridays the Prophet used to recite Alf Lam Mim Tanzil-As-Sajda (in the first Raka) and Hal ata'alal-lnsani i.e. Suratad-Dahr (LXXVI) (in the second Raka), in the Fajr prayer.