Reply to comments by R. Klein on “Open boundary molecular dynamics” R. Delgado-Buscalioni, J. Sablić and M. Praprotnik Eur. Phys. J. Special Topics, 224 12 (2015) 2511-2513 Published online: 21 September 2015 DOI: 10.1140/epjst/e2015-02536-2