Worldwatch Institute & Brown, L. R. (1988). State of the world 2001: A Worldwatch Institute report on progress toward a sustainable society. Earthscan.
Chicago-viite (17. p.)Worldwatch Institute ja Lester Russell Brown. State of the World 2001: A Worldwatch Institute Report on Progress Toward a Sustainable Society. London: Earthscan, 1988.
MLA-viite (9. p.)Worldwatch Institute ja Lester Russell Brown. State of the World 2001: A Worldwatch Institute Report on Progress Toward a Sustainable Society. Earthscan, 1988.
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