Yu, Xian-Chun, De-Lin Sun, and Xiang-Su Li. 2010. “Preparation of Levulinic Acid Using Cellulase and Solid Acid Synergistic Hydrolysis for Rice Straw”. Asian Journal of Chemistry 22 (9):7113-22. https://asianpubs.org/index.php/ajchem/article/view/11959.