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Gibberd FB, Bateson MC.Gibberd FB, et al.Br Med J. 1974 May 25;2(5916):403-5. doi: 10.1136/bmj.2.5916.403.Br Med J. 1974.PMID: 4365958Free PMC article.
Gibberd FB, Page NG, Spencer KM, Kinnear E, Hawksworth JB.Gibberd FB, et al.Br Med J (Clin Res Ed). 1981 Apr 11;282(6271):1196. doi: 10.1136/bmj.282.6271.1196.Br Med J (Clin Res Ed). 1981.PMID: 6788131Free PMC article.Clinical Trial.No abstract available.