Kadhim Hoomod, Haider, et al. “Efficient Neighborhood Function and Learning Rate of Self-Organizing Map (SOM) for Cell Towers Traffic Clustering”. Journal of Al-Qadisiyah for Computer Science and Mathematics, vol. 9, no. 2, Nov. 2017, pp. Comp Page 122 - 130, doi:10.29304/jqcm.2017.9.2.321.