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Black RE, Levine MM, Ferreccio C, Clements ML, Lanata C, Rooney J, Germanier R.Black RE, et al. Among authors: levine mm.Vaccine. 1990 Feb;8(1):81-4. doi: 10.1016/0264-410x(90)90183-m.Vaccine. 1990.PMID: 2180234Clinical Trial.
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