Shamsuddin, Siti Syafrina Nurhidayah, and Nor Afzanizam Samiran. 2021. “Effect of Air and Steam on the Performance of Syngas Yield Using Downdraft Gasification Method”. Progress in Engineering Application and Technology 2 (2): 983-1000. https://penerbit.uthm.edu.my/periodicals/index.php/peat/article/view/1046.