United Nations Economic Commission for Europe. (1979). The Gas Situation in the ECE Region Around the Year 1990. ELSEVIER.
Cita Chicago Style (17a ed.)United Nations Economic Commission for Europe. The Gas Situation in the ECE Region Around the Year 1990. ELSEVIER, 1979.
Cita MLA (8a ed.)United Nations Economic Commission for Europe. The Gas Situation in the ECE Region Around the Year 1990. ELSEVIER, 1979.
Precaución: Estas citas no son 100% exactas.