Não informado. (1971). Educational Media International. International Council for Educational Media.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रNão informado. Educational Media International. London: International Council for Educational Media, 1971.
एमएलए (8वां संस्करण) प्रशस्ति पत्रNão informado. Educational Media International. International Council for Educational Media, 1971.
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