Published online before print June 18, 2002, 10.1073/pnas.132468999
/ Proc. Natl. Acad. Sci. USA, Vol. 99, Issue 13, 8677-8682, June 25, 2002
... 5. Wutz A, and Jaenisch R, "A Shift from Reversible to Irreversible
X...
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