NOVACKÁ, Ľudmila - FRASCH, Alexander. Key Changes in Charter Air Transport on Slovak Market. In Trends and Challenges in the European Business Environment: Trade, International Business and Tourism. International Scientific Conference. Trends and Challenges in the European Business Environment: Trade, International Business and Tourism : Proceedings of the 6th International Scientific Conference, October 17 - 18, 2019 (Mojmírovce, Slovak Republic). - Bratislava : Vydavateľstvo EKONÓM, 2019. ISBN 978-80-225-4646-1, pp. 332-340 CD-ROM.