Musannaf Ibn Abi Shayba 3:1081

Waki’ narrated to us, from Mis’ar, from Habib al-Jarmi, from ‘Amr ibn Salamah, from his father, that they came as a delegation to the Prophet (peace be upon him). When they wanted to depart, they said: We said to him, "O Messenger of Allah, who shall lead us in prayer?" He said: "The one among you who has gathered the most of the Quran, or has taken the most of the Quran." There was no one among them who had gathered as much of the Quran as I had gathered. He said: So they put me forward, and I was a young boy, and I would lead them in prayer while wearing a small cloak. He said: I have not witnessed a gathering of Jurm except that I was their Imam, and I lead their funeral prayers to this day of mine.