Azizi, S.N., et al. “Using of Taguchi Robust Design Method to Optimize Effective Parameters of Methylene Blue Adsorption on ZSM-5 Zeolite”. Asian Journal of Chemistry, vol. 23, no. 1, Sept. 2010, pp. 100-4, https://asianpubs.org/index.php/ajchem/article/view/10148.