Rosadi, W., E. S. Sulaeman, and H. Prasetya. “Multilevel Analysis on Factors Affecting Measles Rubella Immunization Uptake Among Toddlers in Pekanbaru, Indonesia”. Journal of Maternal and Child Health, vol. 4, no. 6, Nov. 2019, pp. 448-60, http://thejmch.com/index.php/thejmch/article/view/275.