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Wiegand T, Gunatilleke CV, Gunatilleke IA, Huth A.Wiegand T, et al.Proc Natl Acad Sci U S A. 2007 Nov 27;104(48):19029-33. doi: 10.1073/pnas.0705621104. Epub 2007 Nov 16.Proc Natl Acad Sci U S A. 2007.PMID: 18024595Free PMC article.