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Carpenter DC, Beaubien AR, Mathieu LF, Hrdina PD.Carpenter DC, et al. Among authors: hrdina pd.Br Med J. 1975 Mar 1;1(5956):516-7. doi: 10.1136/bmj.1.5956.516-e.Br Med J. 1975.PMID: 1125614Free PMC article.No abstract available.