Ali, S. A., S. I. Ali, X. Qiyu, and X. Ming. “Directions to Explore the Principles of Service Innovation: With Various Companies’ Case Study”. Journal of Research in Business, Economics and Management, Vol. 6, no. 3, July 2016, pp. 971-8, http://scitecresearch.com/journals/index.php/jrbem/article/view/822.