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Higgins RM, Goldsmith DJ, Connolly J, Scoble JE, Hendry BM, Ackrill P, Venning MC.Higgins RM, et al. Among authors: ackrill p.Postgrad Med J. 1996 Jan;72(843):41-4. doi: 10.1136/pgmj.72.843.41.Postgrad Med J. 1996.PMID: 8746284Free PMC article.