Muwatta Malik · 263
Sahih · Salim al-Hilali
وَحَدَّثَنِي عَنْ مَالِكٍ، عَنْ هِشَامِ بْنِ عُرْوَةَ، عَنْ أَبِيهِ، عَنْ عَائِشَةَ أُمِّ الْمُؤْمِنِينَ، قَالَتْ كَانَ رَسُولُ اللَّهِ صلى الله عليه وسلم يُصَلِّي بِاللَّيْلِ ثَلاَثَ عَشْرَةَ رَكْعَةً ثُمَّ يُصَلِّي إِذَا سَمِعَ النِّدَاءَ بِالصُّبْحِ رَكْعَتَيْنِ خَفِيفَتَيْنِ .
Yahya related to me from Malik from Hisham ibn Urwa from his father that A'isha, umm al-muminin said, "The Messenger of Allah, may Allah bless him and grant him peace, used to pray thirteen rakas in the night and then would pray two rakas when he heard the adhan for the subh prayer