Jepkorir, C., and G. Kiiru. “Role of Diversification Strategies on Organizational Productivity Among Multinational Oil Firms in Kenya: A Case of Kenolkobil Limited”. The International Journal of Business & Management, vol. 4, no. 10, Oct. 2016, https://internationaljournalcorner.com/index.php/theijbm/article/view/127029.