ABU-SHAMMALA., FARID. “Nonionic/Anionic/Mixed/Surfactants/System/for/Colorimetric/Determination/of/Metal-Dithizone/Complexes”. Asian Journal of Chemistry, vol. 11, no. 2, June 2010, pp. 559-6, https://asianpubs.org/index.php/ajchem/article/view/23320.