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Richards DA, Prichard BN, Boakes AJ, Tuckman J, Knight EJ.Richards DA, et al.Br Heart J. 1977 Jan;39(1):99-106. doi: 10.1136/hrt.39.1.99.Br Heart J. 1977.PMID: 12778Free PMC article.
Richards DA, Prichard BN.Richards DA, et al.Br Med J. 1978 Jun 17;1(6127):1623-4. doi: 10.1136/bmj.1.6127.1623-c.Br Med J. 1978.PMID: 26449Free PMC article.No abstract available.