Yusuf, M.-B. O., and O.-A. S. Oluwatoyin. “User Acceptance of Crash Helmet by Motorcyclists in Malaysia: An Empirical Analysis”. Studia Universitatis Vasile Goldiș Arad, Seria Științe Economice, Vol. 29, no. 1, Mar. 2019, pp. 40-57, https://publicatii.uvvg.ro/index.php/studiaeconomia/article/view/449.