1. Danish defence ministry says its websites hit by cyberattack, December 2022. https://www.reuters.com/world/europe/danish-defence-ministry-says-its-websites-hit-by-cyberattack-2022-12-08/
2. Airline SAS network hit by hackers, says app was compromised, February 2023. https://www.reuters.com/business/aerospace-defense/airline-sas-suffers-cyber-attack-customer-info-leaked-2023-02-14/
3. German airport websites hit by suspected cyber attack, February 2023. https://www.reuters.com/technology/websites-several-german-airports-down-focus-news-outlet-2023-02-16/
4. Lecture Notes in Computer Science;R Alur,1990
5. Lecture Notes in Computer Science;Z Aslanyan,2015