Tuan, Hoang Van. “Some Characteristics about the Process of Nguyen Empiers Established Vietnam Southwestern Sea and Islands Area’s Sovereignty in the 18th Century”. International journal of health sciences 6, no. S2 (March 23, 2022): 17–34. Accessed May 10, 2026. https://sciencescholar.us/journal/index.php/ijhs/article/view/4988.