Sahih al-Bukhari 1541
صحيح البخاري#1541SahihNarrated Salim bin `Abdullah:I heard my father saying, "Never did Allah's Messenger (ﷺ) assume Ihram except at the Mosque, that is, at the Mosque of Dhul-Hulaifa
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Every narration in Sahih al-Bukhari is accepted as Sahih (authentic) by the established status of the book.
In-book reference: 25:28