著者名,書名,版表示,出版者名,出版年,シリーズ名,番号,ISBN,ISSN,URL
Bŭlgarska ent︠s︡iklopedii︠a︡ (Firm),Information Bulgaria : a short encyclopaedia of the People's Republic of Bulgaria,,Pergamon Press,1985,Countries of the world information series,,0080318533,,https://cir.nii.ac.jp/crid/1130000795346630656