The Book of Prayer - Travellers
6/17. Chapter:
Night prayers and the number of rak`ah offered by the Prophet (saws) at night, and that Witr is one rak`ah, and a one-rak`ah prayer is correct
Sahih Muslim
وَحَدَّثَنَا قُتَيْبَةُ بْنُ سَعِيدٍ، حَدَّثَنَا لَيْثٌ، عَنْ يَزِيدَ بْنِ أَبِي حَبِيبٍ، عَنْ عِرَاكِ بْنِ مَالِكٍ، عَنْ عُرْوَةَ، أَنَّ عَائِشَةَ، أَخْبَرَتْهُ أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم كَانَ يُصَلِّي ثَلاَثَ عَشْرَةَ رَكْعَةً بِرَكْعَتَىِ الْفَجْرِ .
'A'isha reported that the Messenger of Allah (ﷺ) used to pray thirteen rak'ahs during the night including the two rak'ahs (Sunan) of the dawn prayer.
Reference : Sahih Muslim 737cIn-book reference : Book 6, Hadith 151USC-MSA web (English) reference : Book 4, Hadith 1606