Cost optimal and nearly zero energy performance requirements for buildings in EstoniaKurnitski, Jarek; Saari, Arto; Kalamees, Targo; Vuolle, Mika; Niemelä, Jouko; Tark, TeetEstonian journal of engineering2013 / p. 183-202 : ill https://artiklid.elnet.ee/record=b2632889*est https://doi.org/10.3176/eng.2013.3.02 Article at Scopus