1. Department of Civil and Environmental Engineering, 77 Massachusetts Avenue, Cambridge, MA 02139.
2. SCN, Quadra2 Lote A, Ed. Corporate Center, 7o. Andar, 70.712-900, Brasília–DF, Brazil.
3. World Bank, 1818 H Street, NW, Washington, DC 20433.
4. Engineering Systems Division, Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139.