Vilotić, D., M. Plančak, Đ. Čupković, V. Mandić, and M. Stefanović. 2003. “FEM Analysis of Upsetting Process by Cyllindrical Dies With Experimental Verification”. Advanced Technologies and Materials 28 (1-2):83-98. https://jged.uns.ac.rs/index.php/atm/article/view/jtp.2003.28.1-2.9.