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Singer JE, Westphal M, Niswander KR.Singer JE, et al. Among authors: westphal m.Child Dev. 1968 Mar;39(1):103-12.Child Dev. 1968.PMID: 4171447No abstract available.
Singer JE, Westphal M, Niswander K.Singer JE, et al. Among authors: westphal m.Obstet Gynecol. 1968 Mar;31(3):417-23. doi: 10.1097/00006250-196803000-00021.Obstet Gynecol. 1968.PMID: 5639199No abstract available.