Não informado. (1967). Educational television international. Centre for Educational Television Overseas.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रNão informado. Educational Television International. London: Centre for Educational Television Overseas, 1967.
एमएलए (8वां संस्करण) प्रशस्ति पत्रNão informado. Educational Television International. Centre for Educational Television Overseas, 1967.
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