Dyfyniad APA
International Energy Agency, Organisation for Economic Co-operation and Development, & ProQuest (Firm). (2009). Energy policies of IEA countries: Portugal 2009 review. OECD/IEA.
Dyfyniad Arddull Chicago
International Energy Agency, Organisation for Economic Co-operation and Development, and ProQuest (Firm). Energy Policies of IEA Countries: Portugal 2009 Review. Paris: OECD/IEA, 2009.
Dyfyniad MLA
International Energy Agency, et al. Energy Policies of IEA Countries: Portugal 2009 Review. OECD/IEA, 2009.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.