Jalaukhan, Ghufran, and Z.D AL-Nafie. “Countable Paracompactness of Nano Topological Space Modeled by Pre-Open Sets Structures”. Journal of Kufa for Mathematics and Computer, vol. 11, no. 1, Mar. 2024, pp. 32-36, doi:10.31642/JoKMC/2018/110106 .