The terminology was used as early as 1918. For example: Taysīr Jabārah (1985). Palestinian Leader Hajj Amin Al-Husayni: Mufti of Jerusalem. Kingston Press. ISBN978-0-940670-10-5. states that Storrs wrote on November 19, 1918 "the Muslim element requested the Grand Mufti to have the name of the Sharif of Mecca mentioned in the Friday prayers as Caliph"