Status on the ground : overview of existing surveys on energy performance related quality and compliance [Online resource]Maivel, Mikk; Kuusk, Kalle; Simson, Raimo; Kurnitski, Jarek; Kalamees, Targo2015 http://qualicheck-platform.eu/wp-content/uploads/2015/06/QUALICHeCK-Report-Overview-of-existing-studies.pdf