1. Struct. Mechanics Associates, Newport Beach, California; formerly Grad. Research Asst., Dept. of Civ. Engrg., Massachusetts Institute of Technology, Cambridge, Mass. 08139
2. Prof., Dept. of Civ. Engrg., Rm 1-238, Massachusetts Institute of Technology, Cambridge, Mass. 08139
3. Edgerton Assoc. Prof., Dept. of Civ. Engrg., Rm 1-232, Massachusetts Institute of Technology, Cambridge, Mass. 08139