Slavov, Stoyan Dimitrov, and Iliyan Velichkov Iliev. “Research on the Variability of the Burnishing Force During Processing Surfaces With 3D Shape by Using Simultaneous 5-Axis Ball-Burnishing Process Implemented on CNC Milling Machine”. ANNUAL JOURNAL OF TECHNICAL UNIVERSITY OF VARNA, BULGARIA 1, no. 1 (December 28, 2017): 6–12. Accessed October 2, 2025. https://aj.tu-varna.bg/index.php/ajtuv/article/view/20.