Improved Sound Absorption Performance of Nonwoven Fabric using Fabric Facing and Air Back CavityAhmad Yusuf Ismail, Muhamad Rafi Omar, Muhamad Arif Anuar Hashim and Muhamad Ridzuan Md RadziMATEC Web Conf., 97 (2017) 01086DOI: https://doi.org/10.1051/matecconf/20179701086