Sahih Muslim 1623
صحيح مسلم#1623SahihSalim reported from his father to be saying:I saw the Messenger of Allah (ﷺ) combining the sunset and Isha' prayers when he was in a hurry on a journey
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: 6:54