edited by Luciano Pietronero and Erio Tosatti. ; sponsored by the International Center for Theoretical Physics(I. C. T. P.). edited by J. M. Bennett and T. Pearcey ; sponsored by the International Council for Computer Communication. edited by B. K. Chakraverty and D. Kaplan ; sponsored by the International Union of Pure and Applied Physics. edited by M. Hildred Blewett ; sponsored by The International Union of Pure and Applied Physics (IUPAP).