Sinaga, Hendrik Gomar, et al. “Effect of Change in Management, Organizational Culture and Transformational Leadership on Employee Performance PT. AdhyaTirta Batam (PT. ATB)”. International Review of Management and Marketing, vol. 8, no. 6, Nov. 2018, pp. 15-23, https://econjournals.com/index.php/irmm/article/view/7081.