Muwatta Malik Book 7, Hadith 29
Yahya related to me from Malik from Nafi from Abdullah ibn Umar
that Hafsa, the wife of the Prophet, may Allah bless him and grant him
peace, told him that the Messenger of Allah, may Allah bless him and
grant him peace, used to pray two quick rakas when the muadhdhin had
finished the adhan for the subh prayer, before the iqama was said for
the prayer.
Malik related to me that Abd ar-Rahman ibn al-Qasim heard his father al-Qasim ibn Muhammad say, "I have prayed witr after dawn."
Malik said, "Only a person who oversleeps so that he does not do the witr prays it after dawn. No one should intentionally make his witr after dawn."
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?' "