Mihajlow, Radko Petrov, and Vladimir Georgiev Demirev. “APPLICATION OF GPS NAVIGATION IN AGRICULTURAL AGGREGATES”. ANNUAL JOURNAL OF TECHNICAL UNIVERSITY OF VARNA, BULGARIA 2, no. 2 (December 21, 2018): 14–19. Accessed October 2, 2025. https://aj.tu-varna.bg/index.php/ajtuv/article/view/84.