Sharkov, George, Christina Todorova, Georgi Koykov, and Ivan Nikolov. "Towards a Robust and Scalable Cyber Range Federation for Sectoral Cyber/Hybrid Exercising: The Red Ranger and ECHO Collaborative Experience." Information & Security: An International Journal 53, no. 2 (2022): 287-302.

Sharkov, George, Christina Todorova, Georgi Koykov, and Georgi Zahariev. Hybrid Exercising for Cyber-Resilient Healthcare and  Cross-Sector Crisis Response Operability In Information Systems and Grid Technologies ISTG, CEUR Workshop Proceedings. Vol. 933., 2021.

Sharkov, George, Christina Todorova, Georgi Koykov, and Georgi Zahariev. "A System-of-Systems Approach for the Creation of a Composite Cyber Range for Cyber/Hybrid Exercising." Information & Security: An International Journal 50, no. 2 (2021): 129-148 .

Sharkov, George, Yavor Papazov, Christina Todorovaa, Georgi Koykov, and Georgi Zahariev. "Cybersecurity Tools for Threat Intelligence and Vulnerability Monitoring for National and Sectoral Analysis." In Information Security in Education and Practice. Cambridge Scholars Publishing, 2020.

Sharkov, George, Yavor Papazov, Christina Todorova, Georgi Koykov, and Georgi Zahariev. "MonSys: A Scalable Platform for Monitoring Digital Services Availability, Threat Intelligence and Cyber Resilience Situational Awareness." Information & Security: An International Journal 46, no. 2 (2020): 155-167.

Sharkov, George, Yavor Papazov, Christina Todorova, Georgi Koykov, Martin Georgiev, and Georgi Zahariev. Cyber Threat Map for National and Sectoral Analysis In Computer and Communications Engineering, Workshop on Information Security 2019, 9th Balkan Conference in Informatics., 2019.

Papazov, Yavor, George Sharkov, Georgi Koykov, and Christina Todorova. "Managing Cyber Education Environments with Serverless Computing." In DIGILIENCE 2019. Sofia, Bulgaria, 2019.