M. Moniruzzaman, A. Rahman, and M. M. Hoq, “Optimization of Medium Ingredients for Keratinolytic Protease Production by <i>Bacillus licheniformis</i> MZK-03 using Statistical Experimental Designs”, Bangla. J. Microbiol., vol. 24, no. 1, pp. 52–56, Oct. 2008.