Não informado. (2009). Main Science and Technology Indicators. Organization for Economic Co-operation and Development.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रNão informado. Main Science and Technology Indicators. Paris: Organization for Economic Co-operation and Development, 2009.
एमएलए (8वां संस्करण) प्रशस्ति पत्रNão informado. Main Science and Technology Indicators. Organization for Economic Co-operation and Development, 2009.
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