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Kristiansen IS, Halvorsen PA, Gyrd-Hansen D.Kristiansen IS, et al.BMC Public Health. 2007 Apr 2;7:48. doi: 10.1186/1471-2458-7-48.BMC Public Health. 2007.PMID: 17407563Free PMC article.
Kristiansen IS, Gyrd-Hansen D.Kristiansen IS, et al.Tidsskr Nor Laegeforen. 2007 Jan 4;127(1):54-7.Tidsskr Nor Laegeforen. 2007.PMID: 17205092Free article.Norwegian.No abstract available.