Amin, L. Muhamad Nadhli, et al. “Comparative Study of Bentonite Filled Acrylonitrile Butadiene Rubber and Carbon Black Filled NBR Composites Properties”. International Journal of Automotive and Mechanical Engineering, vol. 15, no. 3, Oct. 2018, pp. 5468-79, doi:10.15282/ijame.15.3.2018.5.0420.