Παραπομπή σε μορφή APA (7η εκδ.)

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.

Παραπομπή σε μορφή Chicago (17η εκδ.)

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.

Παραπομπή σε μορφή MLA (9th εκδ.)

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.