In his book De caerimoniis aulae Byzantinae ("Book of Ceremonies"), Emperor Constantine VII (913–919) wrote a detailed account of the ceremonies held in the Hagia Sophia by the emperor and the patriarch.
No seu libro De caerimoniis aulae Byzantinae, o emperador Constantino VII (913 a 919) escribiu un relato detallado das cerimonias que levaron a cabo o emperador e o patriarca na igrexa de Santa Sofía.