Musannaf Ibn Abi Shayba 3:1078

Yazid ibn Harun narrated to us, he said: 'Asim informed us, from 'Amr ibn Salamah, who said: "When my people returned from the Messenger of Allah (may Allah bless him and grant him peace), they said: 'He said to us: "Let the one among you who has read the most Quran lead you in prayer."'" He said: "So they called me and taught me the bowing (ruku') and the prostration (sujud). I used to lead them in prayer while wearing a torn cloak." He said: "They used to say to my father: 'Will you not cover the backside of your son from us?'"