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Nataro JP, Deng Y, Maneval DR, German AL, Martin WC, Levine MM.Nataro JP, et al.Infect Immun. 1992 Jun;60(6):2297-304. doi: 10.1128/iai.60.6.2297-2304.1992.Infect Immun. 1992.PMID: 1350273Free PMC article.