Purniawan, Agung, et al. “Functionalization of Carbon Nanotubes As Support Material of Pt CNTs Catalyst for Proton-Exchange Membrane Fuel Cell”. IPTEK The Journal for Technology and Science, vol. 35, no. 1, July 2025, pp. 60-69, https://journal.its.ac.id/index.php/jts/article/view/3107.