Friction and Wear Performance of Lubricants Formulated with Palm Kernel Methyl Ester and Polymeric Additives in Hydrogen-Fuelled Engines. JTSE [Internet]. 2025 Jun. 26 [cited 2026 Jul. 30];12(1):24-30. Available from: https://jtse.utm.my/index.php/jtse/article/view/246