\noindent{\huge \textbf{Declaration}}\\\\\\
I hereby declare that this thesis has been composed by me without any assistance and I have not used any sources or tools other than those cited. 
Furthermore, I declare that I have acknowledged the work of others by providing detailed references.
I also declare that this thesis or parts of it have not been accepted in any other previous application for a degree, project or examination.

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\phantom{ab}Freiburg, \today