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Westerling AL, Turner MG, Smithwick EA, Romme WH, Ryan MG.Westerling AL, et al.Proc Natl Acad Sci U S A. 2011 Aug 9;108(32):13165-70. doi: 10.1073/pnas.1110199108. Epub 2011 Jul 25.Proc Natl Acad Sci U S A. 2011.PMID: 21788495Free PMC article.