Cyril and Methodius among Byzantine missionaries: common features and unique quality - Ivanov, Sergej Arkadʹevič (. The @Cyril and Methodius mission and Europe. - Brno : Archeologický ústav AV ČR, 2014. - 401 Seiten. - Illustrationen, Karten, Faksimiles. - ISBN 80-86023-51-6, 2014)