References
- Valkov , S. S. and Chrnyak , B Ya . 1986 . ‘Welding plastics with ultrasound’ , Moscow : Publ Khimiya .
- Zaitsev , K. I. and Tsyuk , L. N. 1978 . ‘Welding of plastics’ , Moscow : Publ Mashinostroenie .
- Basin , V. S. 1981 . ‘Adhesion strength’ , Moscow : Publ Khimiya .