APA (7th ed.) Zitazioa
International Energy Agency & ProQuest (Firm). (2011). Natural gas information: 2011 with 2010 data. International Energy Agency.
Chicago Style (17th ed.) Zitazioa
International Energy Agency eta ProQuest (Firm). Natural Gas Information: 2011 with 2010 Data. Paris: International Energy Agency, 2011.
MLA (9th ed.) Zitazioa
International Energy Agency eta ProQuest (Firm). Natural Gas Information: 2011 with 2010 Data. International Energy Agency, 2011.
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