Asim, S., M. Hayat, M. Anjum, and Z. Khosso. “Frequency and Factors of Low Vaccination Coverage in Children Visiting a Tertiary Care Facility”. Annals of Jinnah Sindh Medical University, Vol. 5, no. 2, Feb. 2020, pp. 83-86, http://104.215.57.51/index.php/AJSMU/article/view/66.