Shuja, A., A. Shuja, and N. Yazdani. “The Role of Sustainability Practices in Improving Corporate and Sustainability Innovation Performance of the Petroleum Companies of Pakistan”. Journal of Management and Research, Vol. 5, no. 2, Dec. 2018, pp. 1-27, https://ojs.umt.edu.pk/index.php/jmr/article/view/228.