Taher Salim, B., S. Latif Haji, and R. . Saed Hussein. “Factors Affecting Customer Satisfaction in the Internet Service Industry (Exploratory Study of Internet Service Providers in Erbil - Kurdistan Region)”. Polytechnic Journal, vol. 9, no. 1, June 2019, pp. 50-63, doi:10.25156/ptj.v9n1y2019.pp50-63.