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Zhou X, Graham TR.Zhou X, et al. Among authors: graham tr.Proc Natl Acad Sci U S A. 2009 Sep 29;106(39):16586-91. doi: 10.1073/pnas.0904293106. Epub 2009 Sep 15.Proc Natl Acad Sci U S A. 2009.PMID: 19805341Free PMC article.
Baldridge RD, Graham TR.Baldridge RD, et al. Among authors: graham tr.Proc Natl Acad Sci U S A. 2012 Feb 7;109(6):E290-8. doi: 10.1073/pnas.1115725109. Epub 2012 Jan 20.Proc Natl Acad Sci U S A. 2012.PMID: 22308393Free PMC article.