Pasuna, C. . “The Siamese Government and the Administration of the 4 Malay States (Kedah, Perlis, Kelantan and Terengganu), 1873-1910”. Political Science and Public Administration Journal, vol. 12, no. 2, July 2021, pp. 217-40, https://so05.tci-thaijo.org/index.php/polscicmujournal/article/view/240247.