1. Professor, Dept. of Civil and Environmental Engineering, Univ. of Perugia, via G. Duranti 93, 06125 Perugia, Italy.
2. Professor, Dept. of Civil Engineering, Univ. of Toronto, ON, Canada M5S 1A4.
3. Hydraulics Consultant, Perugia, Italy.
4. Assistant Professor, Dept. of Civil and Environmental Engineering, Univ. of Perugia, via G. Duranti 93, 06125 Perugia, Italy.