HENS, H. Applied Building Physics – Boundary Conditions, Building Performance and Material Properties. Berlin: Wilhelm Ernst Sohn, 2011. 308 p. ISBN 978-3-433-02962-6.
EN ISO 6946:2007 Building components and building elements -- Thermal resistance and thermal transmittance -- Calculation method.
The Energy Performance of Buildings Directive (EPBD, Directive 2010/31/EU).