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Cals JW, Hood K, Aaftink N, Hopstaken RM, Francis NA, Dinant GJ, Butler CC.Cals JW, et al. Among authors: francis na.Br J Gen Pract. 2009 Oct;59(567):761-4. doi: 10.3399/bjgp09X472656.Br J Gen Pract. 2009.PMID: 19843422Free PMC article.
Cals JW, Francis NA.Cals JW, et al. Among authors: francis na.BMJ. 2010 Feb 12;340:c574. doi: 10.1136/bmj.c574.BMJ. 2010.PMID: 20154050No abstract available.