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Courcelle J, Carswell-Crumpton C, Hanawalt PC.Courcelle J, et al.Proc Natl Acad Sci U S A. 1997 Apr 15;94(8):3714-9. doi: 10.1073/pnas.94.8.3714.Proc Natl Acad Sci U S A. 1997.PMID: 9108043Free PMC article.
Courcelle CT, Chow KH, Casey A, Courcelle J.Courcelle CT, et al. Among authors: courcelle j.Proc Natl Acad Sci U S A. 2006 Jun 13;103(24):9154-9. doi: 10.1073/pnas.0600785103. Epub 2006 Jun 5.Proc Natl Acad Sci U S A. 2006.PMID: 16754873Free PMC article.