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Staunton DE, Dustin ML, Springer TA.Staunton DE, et al. Among authors: springer ta.Nature. 1989 May 4;339(6219):61-4. doi: 10.1038/339061a0.Nature. 1989.PMID: 2497351
Springer TA.Springer TA.Proc Natl Acad Sci U S A. 1997 Jan 7;94(1):65-72. doi: 10.1073/pnas.94.1.65.Proc Natl Acad Sci U S A. 1997.PMID: 8990162Free PMC article.