Raharjo, P. G., D. B. Hakim, A. H. Manurung, and T. N. Maulana. “The Determinant of Commercial Banks’ Interest Margin in Indonesia: An Analysis of Fixed Effect Panel Regression”. International Journal of Economics and Financial Issues, vol. 4, no. 2, Mar. 2014, pp. 295-08, https://www.econjournals.com/index.php/ijefi/article/view/689.