Musannaf Ibn Abi Shayba 3:3955

Abu Usama narrated to us, from Shu'bah, from Qatadah, from Zurarah ibn Awfa, from Sa'id ibn Hisham, from Aisha, who said: The Messenger of Allah (peace and blessings of Allah be upon him) said: "The two rak'ahs of Fajr are better than the world."