Defence date: 15 December 1989
Examining board: Prof. E. Baltensperger, University of Bern, (co-supervisor) ; Prof. E.M. Claassen, University of Paris and former EUI, (supervisor) ; Prof. D.T. Llewellyn, University of Loughborough ; Prof. S. Martin, EUI ; Prof. R. Richter, University of Saarland