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Trees AH, Howe TE, Grant M, Gray HG.Trees AH, et al. Among authors: howe te.Cochrane Database Syst Rev. 2011 May 11;2011(5):CD005961. doi: 10.1002/14651858.CD005961.pub3.Cochrane Database Syst Rev. 2011.PMID: 21563147Free PMC article.Review.