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Farquhar CW, Spathis GS, Barron JL, Levin GE.Farquhar CW, et al. Among authors: barron jl.Postgrad Med J. 1990 Sep;66(779):714-6. doi: 10.1136/pgmj.66.779.714.Postgrad Med J. 1990.PMID: 2235800Free PMC article.