Bhutto, Rizwan A., and Azra Maqsood. “Customer Services: A Case Study of Cellular Phone Companies in Pakistan”. JISR management and social sciences & economics 5, no. 1 (June 30, 2007): 19–23. Accessed May 11, 2024. https://jisrmsse.szabist.edu.pk/index.php/szabist/article/view/366.