Rančić, Bojan, Predrag Janković, and Velibor Marinković. “Detrmining the Transitonal Area of Square Cups in Oil Hydraulic Forming Process”. Advanced Technologies and Materials 31, no. 1-2 (December 21, 2006): 45–55. Accessed April 3, 2025. https://jged.uns.ac.rs/index.php/atm/article/view/jtp.2006.31.1-2.5.