Maliks Muwatta Book 7, Hadith Number 30.
Section : The Two Rakas of Fajr.
Malik related to me from Yahya ibn Said that A’isha, the wife of the Prophet, may Allah bless him and grant him peace, said, “The Messenger of Allah, may Allah bless him and grant him peace, used to pray the two rakas of the dawn (fajr) so quickly that I would say to myself ‘Has he recited the umm al-Qur’an or not?'”