It is narrated from Sayyiduna Bilal (may Allah be pleased with him) that he used to give the adhan for the Prophet (peace and blessings be upon him), and he would give the adhan like this: "Allah is the Greatest, Allah is the Greatest. I bear witness that there is no true deity except Allah, I bear witness that there is no true deity except Allah." Then he would turn towards the right of the qiblah and say: "I bear witness that Muhammad (peace and blessings be upon him) is the Messenger of Allah, I bear witness that Muhammad (peace and blessings be upon him) is the Messenger of Allah." Then he would turn and face the side behind the qiblah and say: "Come to prayer, come to prayer." Then he would turn to his left and say: "Come to success, come to success." Then he would face the qiblah and say: "Allah is the Greatest, Allah is the Greatest, there is no true deity except Allah." He also used to give the iqamah for the Prophet (peace and blessings be upon him), and he would say the words of the iqamah once each: "Allah is the Greatest, Allah is the Greatest. I bear witness that there is no true deity except Allah, and I bear witness that Muhammad (peace and blessings be upon him) is the Messenger of Allah. Come to prayer, come to success. The prayer has begun. Allah is the Greatest, Allah is the Greatest, there is no true deity except Allah."
Hadith Referenceالمعجم الكبير للطبراني / باب الباء / 1069