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Instanes C, Hetland G, Berntsen S, Løvik M, Nafstad P.Instanes C, et al. Among authors: berntsen s.Indoor Air. 2005 Oct;15(5):356-62. doi: 10.1111/j.1600-0668.2005.00381.x.Indoor Air. 2005.PMID: 16108908
Yangzong, Berntsen S, Bjertness E, Stigum H, Gonggalanzi, Bianba, Nafstad P.Yangzong, et al. Among authors: berntsen s.High Alt Med Biol. 2013 Mar;14(1):31-6. doi: 10.1089/ham.2012.1034.High Alt Med Biol. 2013.PMID: 23537258