I. Mas’ud, S. M. Shafi, M. Z. Awang, N. A. Amir Ramli, and I. A. Subhan, “Parents’ Perception Towards the National COVID-19 Immunisation Programme for Children (PICKids): A Cross-sectional, Internet-Based Survey”, Int. J. Hum. Health Sci., vol. 6, no. 3, pp. 258–268, Jun. 2022.