Worldwatch Institute & Brown, L. R. (1988). State of the world 2001: A Worldwatch Institute report on progress toward a sustainable society. Earthscan.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रWorldwatch Institute और Lester Russell Brown. State of the World 2001: A Worldwatch Institute Report on Progress Toward a Sustainable Society. London: Earthscan, 1988.
एमएलए (9वां संस्करण) प्रशस्ति पत्रWorldwatch Institute और Lester Russell Brown. State of the World 2001: A Worldwatch Institute Report on Progress Toward a Sustainable Society. Earthscan, 1988.
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