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Donald D, Beck JS.Donald D, et al. Among authors: beck js.Nature. 1971 May 21;231(5299):183-4. doi: 10.1038/231183a0.Nature. 1971.PMID: 4930675No abstract available.
Hedley AJ, Ross IP, Beck JS, Donald D, Albert-Recht F, Michie W, Crooks J.Hedley AJ, et al. Among authors: beck js.Br Med J. 1971 Oct 30;4(5782):258-61. doi: 10.1136/bmj.4.5782.258.Br Med J. 1971.PMID: 5171384Free PMC article.