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Wang HY, Wong GW, Chen YZ, Ferguson AC, Greene JM, Ma Y, Zhong NS, Lai CK, Sears MR.Wang HY, et al. Among authors: ferguson ac.CMAJ. 2008 Nov 18;179(11):1133-42. doi: 10.1503/cmaj.071797.CMAJ. 2008.PMID: 19015564Free PMC article.