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Nordløkken A, Pape H, Wentzel-Larsen T, Heir T.Nordløkken A, et al.BMC Public Health. 2013 Jan 22;13:58. doi: 10.1186/1471-2458-13-58.BMC Public Health. 2013.PMID: 23336627Free PMC article.
Sagatun A, Heyerdahl S, Wentzel-Larsen T, Lien L.Sagatun A, et al.BMC Public Health. 2014 Jan 9;14:16. doi: 10.1186/1471-2458-14-16.BMC Public Health. 2014.PMID: 24406098Free PMC article.