1. R. Takeshita and T.L. Hibbard, Friction Plug Welding, United States Patent, Appl. US6213379.B1, 2001.
2. J.A. Littell, Friction Pull Plug and Material Configuration for Anti-Chatter Friction Pull Plug Weld, United States Patent, Appl. US9452491.B1, 2016.
3. S.A. Brooke and V. Bradford, Friction pull plug welding in Aluminum alloys, [in] TWI Conference the Welding Institute, Huntsville, 2012, p. 1795.
4. G.Q. Wang, Y.H. Zhao, L.N. Zhang, J.B. Bai, and R.C. Zhu, A new weld repair technique for friction stir welded aluminum structure: inertia friction pull plug welding, China Welding, 26(2017), No. 4, p. 56.
5. D.F. Metz and M.E. Barkey, Fatigue behavior of friction plug welds in 2195 Al-Li alloy, Int. J. Fatigue, 43(2012), p. 178.