Bekker-Nielsen, T., R. Czichon, C. Høgel, B. Kıvrak, J.M. Madsen, V. Sauer, S.L.
This refers to a group of researchers or contributors named Bekker-Nielsen, R., Czichon, C., Høgel, B., Kıvrak, B., Madsen, J.M., Sauer, V., and S.L.