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Elias KS, Safir GR.Elias KS, et al. Among authors: safir gr.Appl Environ Microbiol. 1987 Aug;53(8):1928-33. doi: 10.1128/aem.53.8.1928-1933.1987.Appl Environ Microbiol. 1987.PMID: 16347418Free PMC article.