Proceedings of the First International Conference on Fracture : held in Sendai, Japan, September 12-17, 1965 / edited by T. Yokobori, T. Kawasaki and J. L. Swedlow ; organized and directed by the Organizing Committee on Fracture ; under the auspices of the United Research Society for Micro and Macro Mechanical Behavior of Metals (Now, the Japanese Society for Strength and Fracture of Materials) and the Japan Society for the Promotion of Science