Sahih Muslim 2198
صحيح مسلم#2198SahihA'isha reported Allah's Apostle (ﷺ) saying:If a company of Muslims numbering one hundred pray over a dead person, all of them interceding for him, their intercession for him will be accepted
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: 11:76