United Nations. Economic Commission for Europe. (1993). Solar Power Systems. United Nations.
Cita Chicago (17th ed.)United Nations. Economic Commission for Europe. Solar Power Systems. New York: United Nations, 1993.
Cita MLA (9th ed.)United Nations. Economic Commission for Europe. Solar Power Systems. United Nations, 1993.
Atenció: Aquestes cites poden no estar 100% correctes.