As-Sa'ib bin Yazid narrated:"The Adhan during the time of Allah's Messenger, Abu Bakr, and Umar was when the Imam came out, [and when] the Iqamah was called for the Salat. Then Uthman [may Allah be pleased with him] added a third call at Az-Zawra

English translation · Jami' at-Tirmidhi