Não informado. (1967). Educational television international. Centre for Educational Television Overseas.
Citação do estilo Chicago (17ª ed.)Não informado. Educational Television International. London: Centre for Educational Television Overseas, 1967.
Citação MLA (8ª ed.)Não informado. Educational Television International. Centre for Educational Television Overseas, 1967.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.