Cajchan, Juraj, Olga Ponisciakova, and Milos Poliak. “Slovak Road Transport from the Point of View of Sustainable Development”. Communications - Scientific letters of the University of Zilina 7, no. 3 (September 30, 2005): 68-71. Accessed April 6, 2026. http://journals.uniza.sk/index.php/communications/article/view/1255.