@book{oai:ir.ide.go.jp:00028740,
 author = {難波, 修},
 month = {},
 note = {Ja/33/Aj68, application/pdf, TPE000200_030},
 publisher = {アジア経済研究所},
 title = {東欧 1.ブルガリア},
 year = {1990}
}