Dyfyniad APA

Brown, L. R. A. (1998). State of the world 1998: A world watch institute report on progress toward a sustainable society.

Dyfyniad Arddull Chicago

Brown, Lester R; Author. State of the World 1998: A World Watch Institute Report on Progress Toward a Sustainable Society. New York, W W Norton & Company, 1998.

Dyfyniad MLA

Brown, Lester R; Author. State of the World 1998: A World Watch Institute Report on Progress Toward a Sustainable Society. 1998.

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