Radzuan, N. Q., M. H. A. Hassan, M. N. Omar, and K. A. Abu Kassim. “The Influence of Helmet Certification in Motorcycle Helmets Protective Performance”. Journal of Mechanical Engineering and Sciences, vol. 18, no. 1, Mar. 2024, pp. 9811-23, doi:10.15282/jmes.18.1.2024.1.0776.