Worldwatch Institute & Brown, L. R. (1998). State of the world 1998: A Worldwatch Institute report on progress toward a sustainable society. Earthscan ; Norton & company.
Chicago-viite (17. p.)Worldwatch Institute ja Lester Russell Brown. State of the World 1998: A Worldwatch Institute Report on Progress Toward a Sustainable Society. London: Earthscan ; Norton & company, 1998.
MLA-viite (8. p.)Worldwatch Institute ja Lester Russell Brown. State of the World 1998: A Worldwatch Institute Report on Progress Toward a Sustainable Society. Earthscan ; Norton & company, 1998.
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