\chapter*{Acknowledgements}

I'd like to thank my supervisor Anders Christensen for a lot of help
and guidance with the project.  Without him, I would have gotten lost.
I also wish to thank my girlfriend, Karianne, without whose support I
wouldn't have finished on time.  In addition, a large thanks goes to
Magni for her help with formal style and \LaTeX.

Trondheim, November 2004\\
Tollef Fog Heen