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.
芝加哥风格引文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引文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.
警告：这些引文格式不一定是100％准确.