Wechuli, D., Okelo, B. and Kangogo, W. (trans.) (2025) “Notions of Subspace Hypercyclicity of Direct Sum of Operators ”, International Journal of Open Problems in Computer Science and Mathematics, 18(3), pp. 95–112. Available at: https://ijopcm.zuj.edu.jo/index.php/IJOPCM/article/view/33 (Accessed: 18 October 2026).