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Kirchhoff F, Carl S, Sopper S, Sauermann U, Mätz-Rensing K, Stahl-Hennig C.Kirchhoff F, et al. Among authors: carl s.Virology. 1999 Feb 1;254(1):61-70. doi: 10.1006/viro.1998.9522.Virology. 1999.PMID: 9927574Free article.
Kirchhoff F, Easterbrook PJ, Douglas N, Troop M, Greenough TC, Weber J, Carl S, Sullivan JL, Daniels RS.Kirchhoff F, et al. Among authors: carl s.J Virol. 1999 Jul;73(7):5497-508. doi: 10.1128/JVI.73.7.5497-5508.1999.J Virol. 1999.PMID: 10364298Free PMC article.