Ndubisi, N. O, and C. N Madu. “CUSTOMER RETENTION STRATEGIES IN THE TELECOMMUNICATIONS INDUSTRY: THE SIGNIFICANCE OF RELATIONSHIP MARKETING”. Global Research Journal of Management and Social Sciences (GRJMSS), vol. 14, no. 2, Feb. 2023, pp. 25-35, https://zapjournals.com/Journals/index.php/grjmss/article/view/524.