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Burman N, Shamaei-Tousi A, Bergström S.Burman N, et al. Among authors: bergstrom s.Infect Immun. 1998 Feb;66(2):815-9. doi: 10.1128/IAI.66.2.815-819.1998.Infect Immun. 1998.PMID: 9453646Free PMC article.