Nguyễn, Khải Hoàn, Phương Thảo Nguyễn, and Văn Hiền Nguyễn. “Ecotourism Development in Tuyen Quang: Case Study of Lam Binh District”. SCIENTIFIC JOURNAL OF TAN TRAO UNIVERSITY 4, no. 10 (April 6, 2021): 61–67. Accessed May 4, 2024. https://tckh.daihoctantrao.edu.vn/index.php/sjttu/article/view/196.