1. ISO 10534-2. Determination of sound absorption coefficient and impedance in impedance tubes – Part 2: transfer-function method. International Organization for Standardization; 1998.
2. Angle-dependent in situ measurement of reflection coefficients using a subtraction technique;Mommertz;Appl Acoust,1995
3. CEN/TS 1793-5. Road traffic noise reducing devices – test method for determining the acoustic performance – intrinsic characteristics – in situ values of sound reflection and airborne sound insulation. European Committee for Standardization; 2003.
4. In situ two-microphone technique for the measurement of the acoustic surface impedance of materials;Allard;Noise Contr Eng J,1989
5. ANSI S1.18-1999 (R2004). Template method for ground impedance. American National Standards Institute; 2004.