United Nations Environment Programme. Division of Early Warning and Assessment. (2006). Geo year book 2006: An overview of our changing environment. UNEP Division of Early Warning and Assessment.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)United Nations Environment Programme. Division of Early Warning and Assessment. Geo Year Book 2006: An Overview of Our Changing Environment. Nairobi: UNEP Division of Early Warning and Assessment, 2006.
توثيق جمعية اللغة المعاصرة MLA (الإصدار التاسع)United Nations Environment Programme. Division of Early Warning and Assessment. Geo Year Book 2006: An Overview of Our Changing Environment. UNEP Division of Early Warning and Assessment, 2006.
تحذير: قد لا تكون هذه الاستشهادات دائما دقيقة بنسبة 100%.