Hyperbolic Equations and Waves

The success of the 1967 Battelle Rencontres was so much appre­ ciated by the participants and organizers of this experimental set-up that it was soon decided to go on with the experiment. Mathematicians and physicists had found a very suitable frame to overcome their natural shyness, to get occasionally interested into each others'' work, to talk 1968 Rencontres have about it, and eventually to kn...