Worldwatch Institute & Brown, L. R. (1998). State of the world 1998: A Worldwatch Institute report on progress toward a sustainable society. Earthscan ; Norton & company.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)Worldwatch Institute و Lester Russell Brown. State of the World 1998: A Worldwatch Institute Report on Progress Toward a Sustainable Society. London: Earthscan ; Norton & company, 1998.
توثيق جمعية اللغة المعاصرة MLA (الطبعة الثامنة)Worldwatch Institute و Lester Russell Brown. State of the World 1998: A Worldwatch Institute Report on Progress Toward a Sustainable Society. Earthscan ; Norton & company, 1998.
تحذير: قد لا تكون هذه الاستشهادات دائما دقيقة بنسبة 100%.