\cleardoublepage

\chapter*{Acknowledgments}
I wish to thank my supervisor Nicolai Viol and Prof. Dr. Wehrle for the opportunity to work on the fascinating subject of this thesis. Without their guidance, their support and especially the challenging and constructive discussions, the thesis would not have been completed with a satisfying result.

Beside my supervisor, I want to thank my team at semantics for allowing me to dedicate my time fully onto the presented topic. Without their efforts, this thesis would not have been possible.

I'm also grateful for all the help of my friends: Mirjam, Kadir, Albert, and Chrissi to proofread the text and dig out all the invisible inconsistencies.

Last, but not least, I must thank my wife Christine for her support and endless patience during the last six months.

