Чернявский, Г., & Чувпило, А. (2017). Professor S. I. Sidelnikov – the eminent Historian of Bulgarian Studies (to the 100 anniversary from the date of a birth). The Journal of V. N. Karazin Kharkiv National University. Series: History, (51), 154-160. Retrieved from https://periodicals.karazin.ua/history/article/view/9890