Bŭlgarska akademii︠a︡ na naukite, Sofia. Bŭlgarska entsiklopedii︠a︡
Bŭlgarska akademii︠a︡ na naukite. Bŭlgarska ent︠s︡iklopedii︠a︡
Bulgarische Enzyklopädie (Firm)
Българска енциклопедия
Bŭlgarska akademii︠a︡ na naukite. Abteilung Bulgarische Enzyklopädie
"Bŭlgarska ent︠s︡iklopedii︠a︡" pri BAN
"Bŭlgarska ent︠s︡iklopedii︠a︡" pri B.A.N
Bulgarian Encyclopaedia (Firm)
Bŭlgarska akademii︠a︡ na naukite. Bulgarian Encyclopaedia
Bulgarian Academy of Science. Bulgarian Encyclopaedia