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-referens (17:e uppl.)Worldwatch Institute och Lester Russell Brown. State of the World 1998: A Worldwatch Institute Report on Progress Toward a Sustainable Society. London: Earthscan ; Norton & company, 1998.
MLA-referens (8:e uppl.)Worldwatch Institute och Lester Russell Brown. State of the World 1998: A Worldwatch Institute Report on Progress Toward a Sustainable Society. Earthscan ; Norton & company, 1998.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.