Ha, Hoa. “Development of Method for Adjusting the National I and II Orders Vertical Network Based on the Local Geoid Hon Dau”. Science and Technology Development Journal 19, no. 2 (June 30, 2016): 5-10. Accessed May 8, 2024. http://stdj.scienceandtechnology.com.vn/index.php/stdj/article/view/661.