Sayyiduna Ziyad bin al-Harith al-Suda'i (may Allah be pleased with him) says: I was with the Messenger of Allah (peace and blessings be upon him); he (peace and blessings be upon him) ordered me and I gave the adhan for Fajr. Then Bilal (may Allah be pleased with him) came to call the iqamah, and the Prophet (peace and blessings be upon him) said: "O Bilal, the brother of Suda' has given the adhan, and whoever gives the adhan should also call the iqamah."
Hadith Referenceالمعجم الكبير للطبراني / باب الزاي / 5267