Muhamad, Aida, et al. “Physical Factors Optimization of Saccharomyces Cerevisiae Fermentation to Enhance Production of Bioethanol: A Review”. Multidisciplinary Applied Research and Innovation, vol. 2, no. 2, May 2021, pp. 266–277, https://publisher.uthm.edu.my/periodicals/index.php/mari/article/view/1849.