Airtightness, air exchange and energy performance in historic residential buildings with different structuresEskola, Lari; Alev, Üllar; Arumägi, Endrik; Jokisalo, Juha; Donarelli, Anna; Sirén, Kai; Kalamees, TargoInternational journal of ventilation2015 / p. 11-26 : ill https://doi.org/10.1080/14733315.2015.11684066 Heating system return temperature effect on heat pump performanceMaivel, Mikk; Kurnitski, Jarek11th International Energy Agency Heat Pump Conference 2014 : 12-16 May 2014, Montréal (Québec), Canada2014 / p. 1-8 : ill