1. C. Conrardy: 8th Int. Conf. on Trends in Welding Research, Pine Mountain, GA, 2008.
2. K. Nakada and M. Ushio: J. Jpn. Weld. Soc., 2002. vol. 71, no. 6, pp. 6-9,
3. W.M. Thomas, E.D. Nicholas, J.C. Needham, M.G. Murch, P. Tem-Plesmith, and C.J. Dawes: Patent Application No. 9125978.8, 1991.
4. H. Okamura and K. Aota: National Conf. of the Japan Welding Society, 2002.
5. A. Elrefaey, M. Takahashi, and K. Ikeuchi: Welding in the World, 2005, vol. 49, nos. 3–4, pp. 93-101.