1. ; Laboratory of Macromolecular Structural Chemistry, Dept. of Chemistry; Catholic University of Leuven; Celestijnenlaan 200F Leuven B-3001 Belgium
2. n.v. De Smet Engineering, Prins Boudewijnlaan 265; Edegem B-2650 Belgium
3. R&D Department; n.v. Vandemoortele Coördination Center; Izegem Belgium