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2. BFRC Guidance Note, www.bfrc.org (2007).
3. Energimaerkning Sekretariat Teknologist Institut, Energimaerkning, Tekniske Bestmmelser for ruder (2005).
4. Energimaerkning Sekretariat Teknologist Institut, Energimaerkning, Energimaerkning, Tekniske Bestmmelser for vinduer (2006).
5. Simplified algorithms for the Italian Energy Rating Scheme for fenestration in Residential Buildings;Maccari;Solar Energy,2000