APA-viite (7. p.)
International Energy Agency. (2004). Energy policies of IEA countries: Portugal 2004 review. OECD/IEA.
Chicago-viite (17. p.)
International Energy Agency. Energy Policies of IEA Countries: Portugal 2004 Review. Paris, Cedex, France: OECD/IEA, 2004.
MLA-viite (9. p.)
International Energy Agency. Energy Policies of IEA Countries: Portugal 2004 Review. OECD/IEA, 2004.
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