United Nations. Economic Commission for Europe. (1991). Energy reforms in Central and Eastern Europe: The first year. United Nations.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)United Nations. Economic Commission for Europe. Energy Reforms in Central and Eastern Europe: The First Year. New York: United Nations, 1991.
توثيق جمعية اللغة المعاصرة MLA (الإصدار التاسع)United Nations. Economic Commission for Europe. Energy Reforms in Central and Eastern Europe: The First Year. United Nations, 1991.
تحذير: قد لا تكون هذه الاستشهادات دائما دقيقة بنسبة 100%.