[1] https://edison.sso.vsb.cz/cz.vsb.edison.edu.study.prepare.web/StudySupportsFileServlet/ae1ff0cc-b553-48ca-84a1-c05b4f18e8f9;1.0/633-Technologie%20tvareni%20II.pdf?inline=true
[2] ALTAN. T., S. OH and H. GEGEL. Metal forming – fundamentals and applications. Metals Park: ASM, 1983.