Gusel, L., and M. Brezočnik. “Effect of Lubrication on the Strain Rate Distribution in Extruded Material”. Advanced Technologies and Materials, vol. 27, no. 1-2, Dec. 2002, pp. 33-40, https://atm-journal.uns.ac.rs/index.php/atm/article/view/jtp.2002.27.1-2.4.