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Muller AE, Havnes IA, Rognli EB, Bukten A.Muller AE, et al.Int J Environ Res Public Health. 2018 Nov 27;15(12):2663. doi: 10.3390/ijerph15122663.Int J Environ Res Public Health. 2018.PMID: 30486386Free PMC article.
Muller AE, Skurtveit S, Clausen T.Muller AE, et al.BMC Med Res Methodol. 2019 Mar 4;19(1):44. doi: 10.1186/s12874-019-0690-3.BMC Med Res Methodol. 2019.PMID: 30832564Free PMC article.