See, Wanhan, Yi Kai Ng, Lin Cui, Yuske Kita, Steven Peng-Lim Ooi, Vernon Lee, Derrick Mok Kwee Heng, and Raymond Tzer Pin Lin. “Singapore’s Efforts to Achieve Measles Elimination in 2018”. Western Pacific Surveillance and Response 12, no. 3 (July 12, 2021): 12. Accessed April 26, 2024. https://ojs.wpro.who.int/ojs/index.php/wpsar/article/view/704.