Não informado. (1956). Half-yearly Bulletin of Electric Energy Statistics for Europe. United Nations, Economic Commission for Europe.
শিকাগো স্টাইল (17 তম সংস্করণ) উদ্ধৃতিNão informado. Half-yearly Bulletin of Electric Energy Statistics for Europe. New York: United Nations, Economic Commission for Europe, 1956.
M.L.A (8 ম সংস্করণ) উদ্ধৃতিNão informado. Half-yearly Bulletin of Electric Energy Statistics for Europe. United Nations, Economic Commission for Europe, 1956.
সতর্কবাণী: সাইটেশন সবসময় 100% নির্ভুল হতে পারে না.