Worapun I, Pianthong K, Thaiyasuit P. Synthesis of biodiesel by two-step transesterification from crude jatropha curcus L.oil using ultrasonic irradiation assisted. Eng Appl Sci Res [internet]. 2012 May 29 [cited 2026 Sep. 25];37(3):169-7. available from: https://ph01.tci-thaijo.org/index.php/easr/article/view/1703