Azretbergenova, Gulmira, and Aziza Syzdykova. “The Dependence of the Kazakhstan Economy on the Oil Sector and the Importance of Export Diversification”. International Journal of Energy Economics and Policy, vol. 10, no. 6, Oct. 2020, pp. 157-63, https://econjournals.com./index.php/ijeep/article/view/9997.