Ngan Ha, Nguyen, & Dang Ngoc Linh.
" Diversity of Medicinal Plants at Phia Oac - Phia Den National Park, Nguyen Binh District, Cao Bang Province." <em>VNU Journal of Science: Earth and Environmental Sciences</em> [Online], 35.1 (2019): n. pag. Web. 24 Apr. 2024