Sahih al-Bukhari 1096
صحيح البخاري#1096SahihNarrated `Abdullah bin Dinar:On traveling, `Abdullah bin `Umar used to offer the prayer on his Mount by signs whatever direction it took. `Abdullah said that the Prophet (ﷺ) used to do so
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: 18:16