S. Alfarisa, R. Safitri, and W. Dwandaru, “Effect of Catalyst Concentrations on the Growth of Carbon Nanotubes from Waste Engine Oil”, EJSMT, vol. 3, no. 1, pp. 6–12, Jun. 2016, Accessed: May 03, 2025. [Online]. Available: https://ejournal.upsi.edu.my/index.php/EJSMT/article/view/39