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McGregor M, Sheldon H, Dwyer D, Stefaniszyn HJ, Novick RJ, Spence PA, Salerno TA.McGregor M, et al. Among authors: stefaniszyn hj.Can Med Assoc J. 1984 Aug 15;131(4):329-30.Can Med Assoc J. 1984.PMID: 6744180Free PMC article.