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Bengtsson C, Ahlqwist M, Andersson K, Björkelund C, Lissner L, Söderström M.Bengtsson C, et al. Among authors: lissner l.Scand J Prim Health Care. 1997 Dec;15(4):214-9. doi: 10.3109/02813439709035031.Scand J Prim Health Care. 1997.PMID: 9444727Free article.