Lim, K.-T., K.-L. Goh, and K.-T. Kwek. “A Comparative Analysis of the Investment- and Speculative-Sovereign Credit Ratings”. International Journal of Business & Economics (IJBE), vol. 8, no. 1, Mar. 2023, pp. 149-74, https://ijbe.ielas.org/index.php/ijbe/article/view/26.