Indarwati, Nanik, and Chandra Wahyuni. “Analysis of Knowledge and Mother’s Ability in Stimulating the Development of Children Aged 18-23 Months”. Journal of Global Research in Public Health, vol. 1, no. 2, Dec. 2016, pp. 51-57, https://www.jgrph.org/index.php/JGRPH/article/view/516.