Volume 5 · Book 58 · Hadith 230
Narrated Jabir bin 'Abdullah: I was present with my two maternal uncles at Al-'Aqaba (where the pledge of allegiance was given). (Ibn 'Uyaina said, "One of the two was Al-Bara' bin Marur.")
— Sahih Bukhari, Volume 5, Book 58: Merits of the Helpers in Madinah (Ansaar), Hadith #230