Abu Uthman al-Yashkuri (may Allah have mercy on him) said: We prayed the morning prayer in the mosque of Banu Rifa'ah and sat down. Then Anas bin Malik (may Allah be pleased with him) came with twenty young men and said: "Have you prayed?" We said: Yes. So Anas (may Allah be pleased with him) ordered one of the young men to give the call to prayer; he gave the adhan and the iqamah, then Anas went forward and led them in prayer.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 5015