Commission of the European Communities. Directorate-General for Energy. (1999). Energy in Europe: European Union energy outlook to 2020. Office for Official Publications of the European Communities.
Chicago-viite (17. p.)Commission of the European Communities. Directorate-General for Energy. Energy in Europe: European Union Energy Outlook to 2020. Luxembourg: Office for Official Publications of the European Communities, 1999.
MLA-viite (9. p.)Commission of the European Communities. Directorate-General for Energy. Energy in Europe: European Union Energy Outlook to 2020. Office for Official Publications of the European Communities, 1999.
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