Sahih Muslim 2698
صحيح مسلم#2698SahihAbdullah b. Buraida (Allah be pleased with him) reported on the authority of his father:I was sitting with the Messenger of Allah (ﷺ) ; the rest of the hadith is the same but with this variation that the (the narrator) said:" Fasts of two months
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: 13:204