Sher, M. G., M. Nadeem, Q. Syed, M. Irfan, and S. Baig. “Alkaline Protease Production from Industrial Waste by Bacillus Subtilis ML-4: Alkaline Protease Production from Industrial Waste”. Biological Sciences - PJSIR, vol. 53, no. 3, Apr. 2010, pp. 146-50, http://v2.pjsir.org/index.php/biological-sciences/article/view/442.