Ivanov, Ivelin. “Tsar Samuel Against Emperor Basil II: Why Did Bulgaria Loose the Battle With the Byzantine Empire at the Beginning of the 11th Century”. Studia Ceranea 1 (December 30, 2011): 205–212. Accessed December 3, 2024. https://czasopisma.uni.lodz.pl/sceranea/article/view/5541.