See, W., Ng, Y. K., Cui, L., Kita, Y., Ooi, S. P.-L., Lee, V., Heng, D. M. K. and Lin, R. T. P. (2021) “Singapore’s efforts to achieve measles elimination in 2018”, Western Pacific Surveillance and Response, 12(3), p. 12. doi: 10.5365/wpsar.2019.10.4.002.