Não informado. (1967). Educational television international. Centre for Educational Television Overseas.
Chicago-referens (17:e uppl.)Não informado. Educational Television International. London: Centre for Educational Television Overseas, 1967.
MLA-referens (8:e uppl.)Não informado. Educational Television International. Centre for Educational Television Overseas, 1967.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.