Hissam, Mohamad Shafiq Aswan, et al. “INFLUENCE OF HARDENER RESIN RATIO TOWARDS FRICTIONAL PROPERTIES OF FIBRE-REINFORCED EPOXY COMPOSITE LAMINATES”. Journal of Transport System Engineering, vol. 7, no. 1, Oct. 2020, pp. 6-12, https://jtse.utm.my/index.php/jtse/article/view/134.