Vasiliev 1951, стр. 233–234 Vasiliev, Aleksandr Aleksandrovich (1951). „Hugh Capet of France and Byzantium”. Dumbarton Oaks Papers. 6: 227. JSTOR1291087. doi:10.2307/1291087.
Poppe 1976, стр. 232 Poppe, Andrzej (1976). „The Political Background to the Baptism of Rus': Byzantine-Russian Relations between 986-89”. Dumbarton Oaks Papers. 30: 195. JSTOR1291395. doi:10.2307/1291395.
jstor.org
Vasiliev 1951, стр. 233–234 Vasiliev, Aleksandr Aleksandrovich (1951). „Hugh Capet of France and Byzantium”. Dumbarton Oaks Papers. 6: 227. JSTOR1291087. doi:10.2307/1291087.
Poppe 1976, стр. 232 Poppe, Andrzej (1976). „The Political Background to the Baptism of Rus': Byzantine-Russian Relations between 986-89”. Dumbarton Oaks Papers. 30: 195. JSTOR1291395. doi:10.2307/1291395.