Sahih Muslim 1322
صحيح مسلم#1322SahihMasruq reported this hadith on the authority of 'A'isha who said:Never did he (the Holy Prophet) say prayer after this in which I did not hear him seeking refuge from the torment of the grave
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: 5:160