Kakovkina, O. 2019 Dec 26. Diplomatic Activity of the People’s Republic of Bulgaria in Ukraine on the basis of the Central State Archives of Public Organizations of Ukraine (TsDAGO). Universum Historiae et Archeologiae = The Universe of History and Archeology = Універсум історії та археології = Универсум истории и археологии ISSN 2664-9950 (Print) ISSN 2707-6385 (Online). [Online] 1:1-2