Maliks Muwatta Book 3, Hadith Number 36.

Section : The Recitation in the Subh Prayer.

Yahya related to me from Malik from Hisham ibn Urwa that his father heard Abdullah ibn Amir ibn Rabia say, “We prayed subh behind Umar ibn al-Khattab and he recited sura Yusuf (Sura 12) and surat al-Hajj (Sura 22) slowly.” I (Hisham’s father) said, “By Allah, then it must have been his habit to get up at the crack of dawn.” He said, “Of course.”