1. Ph.D. Candidate, School of Civil Engineering, Chair of Management and the Technology of Building, Univ. of Belgrade, Bul. Kralja Aleksandra 73, 11000 Belgrade, Serbia. E-mail: milos@grf.bg.ac.yu
2. Professor, Dept. of Informatics and Operations Research, Univ. of Montreal, P.O. Box 6128 Main Post Office, Montreal, Quebec H3C 3J7, Canada. E-mail: nie@iro.umontreal.ca
3. Architect, ACSA Distinguished Professor, School of Architecture, Univ. of Montreal, P.O. Box 6128 Main Post Office, Montreal, Quebec H3C 3J7, Canada (corresponding author). E-mail: colinhdavidson@sympatico.ca