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Dray A, Perkins M.Dray A, et al. Among authors: perkins m.Trends Neurosci. 1993 Mar;16(3):99-104. doi: 10.1016/0166-2236(93)90133-7.Trends Neurosci. 1993.PMID: 7681240Review.
Dray A, Perkins MN.Dray A, et al. Among authors: perkins mn.Agents Actions. 1988 Dec;25(3-4):214-5. doi: 10.1007/BF01965014.Agents Actions. 1988.PMID: 2905864