1. “Friction Welding Methods and Apparatus,”U.K. Patent 1,505,832, 30Mar1978
2. Radial Friction Welding;Nicholas;Proc. Conf. Advances in Welding Processes,1978
3. Radial Friction Welding;Nicholas;Weld. J.,1983
4. Radial Friction Welding for Offshore Pipelines;Dunkerton;Weld. J.,1987