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Boyle AL, Ballard SG, Ward DC.Boyle AL, et al. Among authors: ward dc.Proc Natl Acad Sci U S A. 1990 Oct;87(19):7757-61. doi: 10.1073/pnas.87.19.7757.Proc Natl Acad Sci U S A. 1990.PMID: 2170987Free PMC article.
Lichter P, Ledbetter SA, Ledbetter DH, Ward DC.Lichter P, et al. Among authors: ward dc.Proc Natl Acad Sci U S A. 1990 Sep;87(17):6634-8. doi: 10.1073/pnas.87.17.6634.Proc Natl Acad Sci U S A. 1990.PMID: 2395866Free PMC article.
Lichter P, Cremer T, Tang CJ, Watkins PC, Manuelidis L, Ward DC.Lichter P, et al. Among authors: ward dc.Proc Natl Acad Sci U S A. 1988 Dec;85(24):9664-8. doi: 10.1073/pnas.85.24.9664.Proc Natl Acad Sci U S A. 1988.PMID: 2974158Free PMC article.