Tuan, Tran Quoc, Nguyen Thi Thu Kieu, Le Thi Thuy Ai, Dinh Minh Hiep, and Tran Cat Dong. “Optimization of Medium Composition for Recombinant Nattokinase Production from Bacillus Subtillis by Using Response Surface Methodology”. Academia Journal of Biology 36, no. 1se (August 6, 2014): 130–137. Accessed September 19, 2021. https://vjs.vjs.ac.vn/index.php/vjbio/article/view/4380.