HAO, WENTAO, and WEN YANG. “Comparison Between Crystalline Morphology of Isotactic Polypropylene With Di-P-Methylbenzylidene Sorbitol and Sodium Benzoate”. Asian Journal of Chemistry, vol. 19, no. 7, Mar. 2010, pp. 5385-90, https://asianpubs.org/index.php/ajchem/article/view/13144.