Sahih Muslim 1751
صحيح مسلم#1751SahihAbdullah b. 'Umar reported:A person asked the Messenger of Allah (ﷺ) as I stood between him (the Holy Prophet) and the inquirer and he said: Messenger of Allah, how is the night prayer? He (the Holy Prophet) said: It consists of pairs of rak'ahs, but if you apprehend morning, you should pray one rak'ah and make the end of your prayer as Witr. Then a person asked him (the Holy Prophet) at the end of the year and I was at that place near the Messenger of Allah (ﷺ) ; but I do not know whether he was the same person or another person, but he (the Holy Prophet) gave him the same reply
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: 6:180