1. Professor, School of Community and Regional Planning, Univ. of British Columbia, 433-6333 Memorial Rd., Vancouver BC, Canada V6T 1Z2.
2. Associate Professor, Centre for Human Settlements, School of Community and Regional Planning, Univ. of British Columbia, 1933 West Mall, Second Floor, Vancouver BC, Canada V6T 1Z2.
3. Research Assistant, Centre for Human Settlements, School of Community and Regional Planning, Univ. of British Columbia, 1933 West Mall, Second Floor, Vancouver BC, Canada V6T 1Z2.
4. Professor, Civil and Environmental Engineering, Univ. of Washington, 163 Wilcox Hall, Box 352700, Seattle, WA 98195-2700.