1. School of Mechanical and Civil Engineering, Curtin University, GPO Box U9187 Perth, WA 6845, Australia
2. Birmingham City University, Business School, Galton Building, City North Campus, Perry Barr, Birmingham, B42 2SU, UK
3. Business School, Brunel University, Uxbridge, Middlesex UB8 3PH, UK
4. Department of Construction Engineering, Universitat Politècnica de Catalunya, Barcelona, Spain