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Backer V, Sverrild A, Porsbjerg C.Backer V, et al. Among authors: porsbjerg c.Immunol Allergy Clin North Am. 2013 Aug;33(3):347-62, viii. doi: 10.1016/j.iac.2013.02.005. Epub 2013 Mar 29.Immunol Allergy Clin North Am. 2013.PMID: 23830129Review.