Tzagkarakis, Stylianos Ioannis. “The Role of Federalism in European Integration in the Context of Contemporary Multifaceted Challenges”. Advances in Social Sciences Research Journal 8, no. 8 (August 11, 2021): 76–80. Accessed December 8, 2025. https://www.journals.scholarpublishing.org/index.php/ASSRJ/article/view/10585.