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Lee A, Bar-Zeev N, Walker SP, Permezel M.Lee A, et al. Among authors: walker sp.Obstet Gynecol. 2003 Nov;102(5 Pt 2):1197-9. doi: 10.1016/s0029-7844(03)00700-2.Obstet Gynecol. 2003.PMID: 14607055