Sahih Muslim 1727
صحيح مسلم#1727Sahihحَدَّثَنَا ابْنُ نُمَيْرٍ، حَدَّثَنَا أَبِي، حَدَّثَنَا حَنْظَلَةُ، عَنِ الْقَاسِمِ بْنِ مُحَمَّدٍ، قَالَ سَمِعْتُ عَائِشَةَ، تَقُولُ كَانَتْ صَلاَةُ رَسُولِ اللَّهِ صلى الله عليه وسلم مِنَ اللَّيْلِ عَشَرَ رَكَعَاتٍ وَيُوتِرُ بِسَجْدَةٍ وَيَرْكَعُ رَكْعَتَىِ الْفَجْرِ فَتِلْكَ ثَلاَثَ عَشْرَةَ رَكْعَةً .
It is reported on the authority of 'A'isha that the prayer of Allah's Messenger (ﷺ) in the night consisted of ten rak'ahs. He observed a Witr and two rak'ahs (of Sunan) of the dawn prayer, and thus the total comes to thirteen rak'ahs
Scholarly Authentication
The label above is the grade most of these scholars gave — one dissenting opinion no longer speaks for all of them. If any scholar calls a narration fabricated, that verdict is shown instead, whatever the others say. Each scholar's own wording:
Every narration in Sahih Muslim is accepted as Sahih (authentic) by the established status of the book.
In-book reference: 6:156