Харченко В, Чинченко Ю, Райчев С, Луппо О. Risk assessment in air navigation system methods of the theory of fuzzy sets. Proceedings of National Aviation University [Internet]. 2008 Jan. 1 [cited 2026 May 30];34(1):3-7. Available from: http://jrnl.kai.edu.ua/index.php/visnik/article/view/1521