Materna, Matúš, Benedikt Badánik, Alena Novák Sedláčková, and Andrea Maternová. “Commercialisation of Air Navigation Service Providers – Evidence from Europe”. Promet - Traffic&Transportation 33, no. 5 (October 8, 2021): 647-659. Accessed April 25, 2024. https://traffic.fpz.hr/index.php/PROMTT/article/view/3868.