Some parts of this thesis have been presented at Sinn und Bedeutung 5 in Amsterdam and are included in the proceedings of NELS 31. They have been developed in joint work with Andreas Haida. I have to thank him for the fruitful discussions and especially for his contributions to the syntactic and grammar-theoretic considerations of the approach.
This thesis was written in March 2001, and until the time of publication some time has passed. In the meantime, several publications which are relevant for the subject of this thesis have been made. I have tried to integrate them into the thesis as good as possible afterwards, but I am sure that I will also have missed out relevant new publications for which I apologise.