What role did the Prophet Muhammad (saw) have in the decision to add a third Adhan at Az-Zaura' during the Caliphate of `Uthman?
 Narrated As-Saib bin Yazid:                     In the lifetime of the Prophet, Abu Bakr and `Umar, the Adhan for the Jumua prayer used to be pronounced when the Imam sat on the pulpit. But during the Caliphate of `Uthman when the Muslims increased in number, a third Adhan at Az-Zaura' was added. Abu `Abdullah said, "Az-Zaura' is a place in the market of Medina."