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Чикаго-гийн эшлэл (17 дахь хэвлэлт)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 -ийн эшлэл (9 дэх хэвлэлт)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.
Анхааруулга: Эдгээр ишлэлүүд үргэлж 100% үнэн зөв биш байж магадгүй.