Minneapolis. Public Library. Environmental Conservation Library. (1974). ECOL book catalog: Environmental conservation library. American Library Association.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)Minneapolis. Public Library. Environmental Conservation Library. ECOL Book Catalog: Environmental Conservation Library. Chicago: American Library Association, 1974.
توثيق جمعية اللغة المعاصرة MLA (الإصدار التاسع)Minneapolis. Public Library. Environmental Conservation Library. ECOL Book Catalog: Environmental Conservation Library. American Library Association, 1974.
تحذير: قد لا تكون هذه الاستشهادات دائما دقيقة بنسبة 100%.