Badrulhisam NH, Nessiem Ehab Frere, Ismail MY, Abdullah AA, W Sawangsri. Effect of B30 Palm Oil Methyl Ester Biodiesel with Isobutanol Fuel Additive on Engine Performance of a Diesel Engine. IJIE. 2024;16(2):363-372. Accessed August 7, 2026. https://journal.uthm.edu.my/index.php/ijie/article/view/17404