Messenger of Allah ﷺ used to offer thirteen rakʿat in the night prayer and on hearing the Adhan for the morning prayer, he used to offer two light rakʿat.  

كَانَ رَسُولُ اللَّهِ ﷺ يُصَلِّي بِاللَّيْلِ ثَلاَثَ عَشْرَةَ رَكْعَةً ثُمَّ يُصَلِّي إِذَا سَمِعَ النِّدَاءَ بِالصُّبْحِ رَكْعَتَيْنِ خَفِيفَتَيْنِ  

The Messenger of Allah ﷺ used to pray thirteen rak'ahs during the night ; he then offered two light rak'ahs of prayer when he heard the call to the dawn prayer.  

كَانَ رَسُولُ اللَّهِ ﷺ 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 ﷺ used to pray thirteen rakas in the night and then would pray two rakas when he heard the adhan for the subh prayer."  

قَالَتْ كَانَ رَسُولُ اللَّهِ ﷺ يُصَلِّي بِاللَّيْلِ ثَلاَثَ عَشْرَةَ رَكْعَةً ثُمَّ يُصَلِّي إِذَا سَمِعَ النِّدَاءَ بِالصُّبْحِ رَكْعَتَيْنِ خَفِيفَتَيْنِ  

The Messenger of Allah ﷺ used to pray thirteen rak'ahs during the night ; he then offered two light rak'ahs of prayer when he heard the call to the dawn prayer. (Using translation from Abū Dāʾūd 1339)  

أَنَّهَا قَالَتْ كَانَ رَسُولُ اللهِ ﷺ يُصَلِّي بِاللَّيْلِ ثَلَاثَ عَشْرَةَ رَكْعَةً ثُمَّ يُصَلِّي إِذَا سَمِعَ النِّدَاءَ بِالصُّبْحِ رَكْعَتَيْنِخَفِيفَتَيْنِ  

The Messenger of Allah ﷺ used to pray thirteen rak'ahs during the night ; he then offered two light rak'ahs of prayer when he heard the call to the dawn prayer. (Using translation from Abū Dāʾūd 1339)  

إِنَّ رَسُولَ اللهِ ﷺ كَانَ «يُصَلِّي بِاللَّيْلِ ثَلَاثَ عَشْرَةَ رَكْعَةً ثُمَّ يُصَلِّي إِذَا سَمِعَ النِّدَاءَ بِالصُّبْحِ رَكْعَتَيْنِ خَفِيفَتَيْنِ»