Worldwatch Institute & Brown, L. R. (1990). State of the world 1990: A Worldwatch Institute report on progress toward a sustainable society. W. W. Norton and Company.
Čikaški stil citiranja (17. izdanje)Worldwatch Institute i Lester Russell Brown. State of the World 1990: A Worldwatch Institute Report on Progress Toward a Sustainable Society. New York: W. W. Norton and Company, 1990.
MLA način citiranja (9. izdanje)Worldwatch Institute i Lester Russell Brown. State of the World 1990: A Worldwatch Institute Report on Progress Toward a Sustainable Society. W. W. Norton and Company, 1990.
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