Sahih Muslim 779
صحيح مسلم#779SahihUbayy Ibn Ka'b reported:I arked the Messenger of Allah (ﷺ) about a man who has sexual intercourse with his wife, but leaves her before orgasm. Upon this he (the Holy Prophet) said: He should wash the secretion of his wife, and then perform ablution and ofier prayer
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: 3:101