1. Mgr., Regional Transportation Planning Dept., Parsons Brinckerhoff, Quade & Douglas, One Penn Plaza, New York, N.Y. 10119.
2. Grad. Research Asst., Dept. of Civ. Engrg., Transportation Program, Princeton Univ., Princeton, N.J. 08544.
3. Grad. Research Asst., Dept. of Civ. Engrg., Transportation Program, Princeton Univ., Princeton, N.J. 08544