1. European Commission, “Energy efficiency in buildings,” 2020. [Online]. Available: https://ec.europa.eu/info/sites/default/files/energy_climate_change_environment/events/documents/in_focus_energy_efficiency_in_buildings_en.pdf.
2. European Commission, “Directive 2002/91/EC of the European Parliament and ofthe Council of 16 December 2002 on the energy performance of buildings.”.
3. European Commission, “Directive 2010/31/EU of the European Parliament and of the Council of 19 May 2010 on the energy performance of buildings.”.
4. European Union, “Clean energy for all Europeans,” 2019. 10.2833/9937.
5. European Commission, “Directive (EU) 2018/844 of the European Parliament and ofthe Council of 30 may 2018 amending directive 2010/31/EU on the energy performance of buildings and directive 2012/27/EU on energy efficiency.” [Online]. Available: https://eur-lex.europa.eu/legal-content/EN/TXT/PDF/?uri=CELEX:32018L0844&from=EN.