1. Department of Construction Management and Engineering; University of Twente; P.O. Box 217, 7500 AE Enschede The Netherlands
2. B.V. Kanaalkruising Sluiskil; Koegorsstraat 1C; 4538 PK Terneuzen The Netherlands
3. Witteveen + Bos Raadgevende ingenieurs B.V.; P.O. Box 233, 7400 AE Deventer The Netherlands