ŠEMKOV, G. Kirilometodievistika simpozium. Vtori meždunaroden kongres po bălgaristika, Sofija, 23 maj - 3 juni 1986 g.; Hoffer, Angelika, Edle von Sulmtal - Michail Margaritov: Za Kiril i Metodij. An Attempt to Establish the Nationality of the Slav Apostles Constantine and Methodius and an Explanation of Some Circumstances Related to This Question. Südost-Forschungen, [S. l.], v. 1, n. 1, p. 380–381, 2021. Disponível em: http://bsb0sit-zepweb01.bsb.lrz.de/portal/index.php/sof/article/view/8324. Acesso em: 9 mai. 2024.