United Nations. Economic Commission for Europe. (1991). Energy reforms in Central and Eastern Europe: The first year. United Nations.
Cita Chicago (17th ed.)United Nations. Economic Commission for Europe. Energy Reforms in Central and Eastern Europe: The First Year. New York: United Nations, 1991.
Cita MLA (9th ed.)United Nations. Economic Commission for Europe. Energy Reforms in Central and Eastern Europe: The First Year. United Nations, 1991.
Atenció: Aquestes cites poden no estar 100% correctes.