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Spencer DA, Green SE, Evans JM, Piper PJ, Costello JF.Spencer DA, et al. Among authors: piper pj.Clin Exp Allergy. 1990 Sep;20(5):525-32. doi: 10.1111/j.1365-2222.1990.tb03145.x.Clin Exp Allergy. 1990.PMID: 2253083