[1] ALTAN, T., G. NGAILE and G. SHEN. Cold and Hot Forging: Fundamentals and Applications. Materials Park Ohio: ASM International, 2005. ISBN 0-87170-805-1.
[2] SEMIATIN, S.L. et al. Metalworking: Bulk Forming. Materials Park Ohio: ASM International, 2005. ISBN 978-0-87170-708-6 .