Toibah, A. R., F. Misran, A. Shaaban, and Z. Mustafa. “Effect of PH Condition During Hydrothermal Synthesis on the Properties of Hydroxyapatite from Eggshell Waste”. Journal of Mechanical Engineering and Sciences, vol. 13, no. 2, June 2019, pp. 4958-69, doi:10.15282/jmes.13.2.2019.14.0411.