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Nicholson KG, Colegate AE, Podda A, Stephenson I, Wood J, Ypma E, Zambon MC.Nicholson KG, et al. Among authors: zambon mc.Lancet. 2001 Jun 16;357(9272):1937-43. doi: 10.1016/S0140-6736(00)05066-2.Lancet. 2001.PMID: 11425416Clinical Trial.