1. Skinner , Wickham , “ Manufacturing the Formidable Competitive Weapon ”, John Wiley & Sons, 1985
2. Bernhardt , Ernest “ Computer Aided Engineering for Injection Molding ”, Hanser, 1983
3. Altan , T. , Oh , S. , and Gegel , H. “ Metal forming. Fundamentals and Applications ”, American Society for Metals, Metals Park, Ohio y 1980 P– 220 – 223