Rock 2006, p. 272, "Seven years later, a council of Russian bishops elected Iona of Riazan as metropolitan without reference to Constantinople, an implicit declaration of autocephaly, however respectful their subsequent explanations". Rock, Stella (17 August 2006). Angold, Michael (ed.). The Cambridge History of Christianity: Volume 5, Eastern Christianity. Cambridge University Press. pp. 253–275. ISBN978-0-521-81113-2.