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Powell DA, Hu PC, Wilson M, Collier AM, Baseman JB.Powell DA, et al. Among authors: hu pc.Infect Immun. 1976 Mar;13(3):959-66. doi: 10.1128/iai.13.3.959-966.1976.Infect Immun. 1976.PMID: 178600Free PMC article.