CONTEMPORARY PHYSICS: TRIESTE SYMPOSIUM 1968, VOL.I (A. Abrikosov, P.W. Anderson, J.G. Bolton, E.M. Burbidge, B.F. Burke, A.G.W. Cameron, B. Coppi, P.G. de Gennes, S. Deser, R.H. Dicke, P.A.M. Dirac, S. Doniach, T. Dupree, R.A. Ferrell, M.E. Fisher, V.A.