Луппо ОЄ, Пігур ЯА. Definition of indicators to assess the operational safety and environment definition of the elements of air navigation systems. Proceedings of National Aviation University [Internet]. 2013 May 11 [cited 2024 Dec. 20];55(2):27-32. Available from: https://jrnl.nau.edu.ua/index.php/visnik/article/view/5404