Sahih al-Bukhari 3112
صحيح البخاري#3112SahihMuhammad bin Suqa:I heard Mundhir at-Tawri reporting Ibn Hanafiya who said, "My father sent me saying, 'Take this letter to `Uthman for it contains the orders of the Prophet (ﷺ) concerning the Sadaqa
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: 57:21