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Heiberg A, Slack J.Heiberg A, et al. Among authors: slack j.Br Med J. 1977 Aug 20;2(6085):493-5. doi: 10.1136/bmj.2.6085.493.Br Med J. 1977.PMID: 890365Free PMC article.
Leonard JV, Whitelaw AG, Wolff OH, Lloyd JK, Slack J.Leonard JV, et al. Among authors: slack j.Br Med J. 1977 Jun 18;1(6076):1566-8. doi: 10.1136/bmj.1.6076.1566.Br Med J. 1977.PMID: 871667Free PMC article.