Todorov, Vyacheslav. “Social Aspect of Development of the Bulgarian Ethnogeographic System of the Ukrainian Danube”. Journal of Danubian Studies and Research 13, no. 2 (October 31, 2023): 188–200. Accessed December 19, 2024. https://dj.univ-danubius.ro/index.php/JDSR/article/view/2522.