Não informado. (1956). Annual bulletin of electric energy statistics for Europe. United Nations, Economic Commission for Europe.
Lua i Stíl Chicago (17ú heag.)Não informado. Annual Bulletin of Electric Energy Statistics for Europe. New York: United Nations, Economic Commission for Europe, 1956.
Lua MLA (8ú heag.)Não informado. Annual Bulletin of Electric Energy Statistics for Europe. United Nations, Economic Commission for Europe, 1956.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.