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Hawkins CJ, Uren AG, Häcker G, Medcalf RL, Vaux DL.Hawkins CJ, et al. Among authors: hacker g.Proc Natl Acad Sci U S A. 1996 Nov 26;93(24):13786-90. doi: 10.1073/pnas.93.24.13786.Proc Natl Acad Sci U S A. 1996.PMID: 8943013Free PMC article.