“Electric Spark Alloying of Structural Alloyed Steel 30HGSNA for Parts of Friction Units”. Visnyk of Vinnytsia Politechnical Institute, no. 5 (October 31, 2019): 81–84. Accessed November 15, 2026. https://vpi.sprava.net/index.php/visnyk/article/view/2420.