1. Flat-walled graded density anechoic lining;Davern,1980
2. Sound absorbing materials;Zwicker,1949
3. Comparison of three methods for measuring acoustic properties of bulk materials;Smith;Journal of Acoustical Society of America,1983
4. Acoustical characteristics of fibrous absorbent materials;Delany;National Physical Laboratory Aero Report Ac37,1969
5. A unified theory of sound absorption in fibrous porous materials;Bies,1981