Afzal, S. ., A. K. . Chandio, S. . Shaikh, M. . Bhand, B. A. . Ghumro, and A. K. . khuhro. “Factors Behind Brand Switching in Cellular Networks”. International Journal of Asian Social Science, vol. 3, no. 2, Feb. 2013, pp. 299-07, https://archive.aessweb.com/index.php/5007/article/view/2417.