Luppo, Alexandr, Gennadiy Argunov, and Oleksandr Prygara. “EUROPEAN CENTRALIZED SERVICES OF AIR NAVIGATION SYSTEM”. Proceedings of National Aviation University (archive) 60, no. 3 (October 1, 2014): 43–48. Accessed May 28, 2026. http://jrnl.kai.edu.ua/index.php/visnik/article/view/7563.