1. Korea Basic Science Institute, 52 Yeoeun-Dong Taejeon, 305-333, Korea
2. Lawrence Livermore National Laboratory P.O. Box 808, Livermore, California 94551
3. General Atomics, P.O. Box 85608, San Diego, California 92186
4. New York University Courant Institute of Mathematical Science, New York, New York 10012