Sahih Muslim 1614
صحيح مسلم#1614SahihIbn 'Umar reported:I saw the Messenger of Allah (ﷺ) praying (Nafl prayer) on a donkey's back while his face was turned towards Khaibar
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: 6:45