1. Aalto University, HIIT, Finland. jori.bomanson@aalto.fi
2. University of Potsdam, Germany. gebser@cs.uni-potsdam.de
3. Aalto University, HIIT, Finland. tomi.janhunen@aalto.fi
4. University of Potsdam, Germany. kaufmann@cs.uni-potsdam.de
5. University of Potsdam, Germany; INRIA Rennes, torsten@cs.uni-potsdam.de