Nyirenda, G., N. Tamaldin, and M. Zakaria. “The Impact of Biodiesel Blend Variation Contamination to Engine Friction, Wear, Performance and Emission”. International Journal of Automotive and Mechanical Engineering, vol. 18, no. 1, Apr. 2021, pp. 8592 -, doi:10.15282/ijame.18.1.2021.18.0653.