Sahih al-Bukhari 1514
صحيح البخاري#1514SahihNarrated Ibn `Umar:I saw that Allah's Messenger (ﷺ) used to ride on his Mount at Dhul Hulaifa and used to start saying, "Labbaik" when the Mount stood upright
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: 25:2