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Spencer PS, Ludolph AC, Kisby GE.Spencer PS, et al.Ann N Y Acad Sci. 1992 May 11;648:154-60. doi: 10.1111/j.1749-6632.1992.tb24533.x.Ann N Y Acad Sci. 1992.PMID: 1322079Review.
Spencer PS, Palmer VS, Herman A, Asmedi A.Spencer PS, et al.Lancet. 1987 Nov 28;2(8570):1273-4. doi: 10.1016/s0140-6736(87)91883-6.Lancet. 1987.PMID: 2890883No abstract available.