Böhmer, M. M., Buchholz, U., Corman, V. M., Hoch, M., Katz, K., Marosevic, D. V., Böhm, S., Woudenberg, T., Ackermann, N., Konrad, R., Eberle, U., Treis, B., Dangel, A., Bengs, K., Fingerle, V., Berger, A., Hörmansdorfer, S., Ippisch, S., Wicklein, B., Grahl, A., Pörtner, K., Muller, N., Zeitlmann, N., Boender, T. S., Cai, W., Reich, A., an der Heiden, M., Rexroth, U., Hamouda, O., Schneider, J., Veith, T., Mühlemann, B., Wölfel, R., Antwerpen, M., Walter, M., Protzer, U., Liebl, B., Haas, W., Sing, A., Drosten, C., & Zapf, A. (2020). investigation of a COVID-19 outbreak in Germany resulting from a single travel-associated primary case: a case series. Lancet infectious diseases, 20(8), 920–928. http://access.bl.uk/ark:/81055/vdc_100105768478.0x00001d