1. G.R. Irwin and J.A. Kies, Welding Journal, 33, (April 1954), 1935?1985.
2. G.R. Irwin, ASME Paper No. 57-APM-22, Presented at the Applied Mechanics Summer Conference, Berkely, CA (June 1957).
3. C.Y. Li and R.P. Wei, Materials Research and Standards, 6 (1966) 392.
4. J.D. Landes and R.P. Wei, International Journal of Fracture, 9 (1973) 277?293.
5. W.G. Clark and L.C. Ceschini, Materials Evaluation (August 1968) 180.