IUCN--The World Conservation Union, (Nature Conservancy (U.S, & World Bank. (2005). ?How much is an ecosystem worth: Assessing the economic value of conservation. IUCN, the Nature Conservancy, the World Bank.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)IUCN--The World Conservation Union, (Nature Conservancy (U.S, و World Bank. ?How Much Is an Ecosystem Worth: Assessing the Economic Value of Conservation. .Washington, DC: IUCN, the Nature Conservancy, the World Bank, 2005.
توثيق جمعية اللغة المعاصرة MLA (الإصدار التاسع)IUCN--The World Conservation Union, et al. ?How Much Is an Ecosystem Worth: Assessing the Economic Value of Conservation. IUCN, the Nature Conservancy, the World Bank, 2005.
تحذير: قد لا تكون هذه الاستشهادات دائما دقيقة بنسبة 100%.