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Woo PC, Lau SK, Tsoi HW, Chen ZW, Wong BH, Zhang L, Chan JK, Wong LP, He W, Ma C, Chan KH, Ho DD, Yuen KY.Woo PC, et al.Vaccine. 2005 Oct 10;23(42):4959-68. doi: 10.1016/j.vaccine.2005.05.023.Vaccine. 2005.PMID: 15993989Free PMC article.