International Review for Environmental Strategies. Institute for Global Environmental Strategies.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रInternational Review for Environmental Strategies. Institute for Global Environmental Strategies.
एमएलए (9वां संस्करण) प्रशस्ति पत्रInternational Review for Environmental Strategies. Institute for Global Environmental Strategies.
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