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Schaffert DA, Johnsen SD, Johnson PC, Drayer BP.Schaffert DA, et al. Among authors: drayer bp.Neurology. 1989 Mar;39(3):440-2. doi: 10.1212/wnl.39.3.440.Neurology. 1989.PMID: 2927660
Williams KD, Drayer BP, Johnsen SD, Johnson PC.Williams KD, et al. Among authors: drayer bp.AJNR Am J Neuroradiol. 1990 Mar-Apr;11(2):400-2.AJNR Am J Neuroradiol. 1990.PMID: 2107727Free PMC article.No abstract available.