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Rettig EM, Fick SE, Hijmans RJ.Rettig EM, et al. Among authors: hijmans rj.Heliyon. 2020 May 13;6(5):e03829. doi: 10.1016/j.heliyon.2020.e03829. eCollection 2020 May.Heliyon. 2020.PMID: 32426532Free PMC article.