Sahih Muslim 1723
صحيح مسلم#1723SahihAbu Salama b. Abd al-Rahman asked 'A'isha about the (night) prayer of the Messenger of Allah (ﷺ) during the month of Ramadan. She said:The Messenger of Allah (ﷺ) did not observe either in Ramadan or in other months more than eleven rak'ahs (of the night prayer). He (in the first instance) observed four rak'ahs. Ask not about their excellence and their length (i. e. these were matchless in perfection and length). He again observed four rak'ahs, and ask not about their excellence and their length. He would then observe three rak'ahs (of the Witr prayer). 'A'isha again said: I said: Messenger of Allah, do you sleep before observing the Witr prayer? He said: O 'A'isha, my eyes sleep but my heart does not sleep
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Every narration in Sahih Muslim is accepted as Sahih (authentic) by the established status of the book.
In-book reference: 6:152