Sahih Muslim 6281
صحيح مسلم#6281SahihA'isha reported that Allah's Apostle (ﷺ) did not marry any other woman till her (Khadija's) death
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: 44:111