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2. EUR-Lex (2023, July 16). EU Directive 2018/844 of the European Parliament and of the Council of 30 May 2018 Amending Directive 2010/31/EU on the Energy Performance of Buildings and Directive 2012/27/EU on Energy Efficiency. Available online: https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=uriserv:OJ.L_.2018.156.01.0075.01.ENG.
3. European Commission (2023, September 06). Energy Efficiency First Principle. Available online: https://energy.ec.europa.eu/topics/energy-efficiency/energy-efficiency-targets-directive-and-rules/energy-efficiency-first-principle_en.
4. European Commission (2023, July 16). A European Green Deal. Available online: https://ec.europa.eu/info/strategy/priorities-2019-2024/european-green-deal_en.
5. European Parliament (2023, September 06). Initial Appraisal of a European Commission Impact Assessment. Available online: https://www.europarl.europa.eu/RegData/etudes/BRIE/2021/699462/EPRS_BRI(2021)699462_EN.pdf.