N. , N. . „Legal Sources and Bibliography of Bulgaria [Praeger Publications in Russian History and World Communism, 18]“. Südost-Forschungen, Bd. 1, Nr. 1, November 2021, S. unbekannt, http://bsb0sit-zepweb01.bsb.lrz.de/portal/index.php/sof/article/view/13254.