W. KOSIŃSKI, Z. NOWAK, and R. PĘCHERSKI, “Professor Piotr Perzyna - in memoriam”, Eng. Trans., vol. 61, no. 3, pp. 167–171, Sep. 2013, Accessed: Jun. 10, 2025. [Online]. Available: https://et3.ippt.pan.pl/index.php/et/article/view/13