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Langston AL, Campbell MK, Entwistle VA, Skea Z.Langston AL, et al. Among authors: skea z.BMC Health Serv Res. 2005 May 24;5:39. doi: 10.1186/1472-6963-5-39.BMC Health Serv Res. 2005.PMID: 15913460Free PMC article.