Ngan, Tu, 		Hieu, Nguyen, 		Hiep, Nguyen, 		Long, Phan, AND 		Thanh, Nguyen.
" Population Status of Michelia citrata in Cao Ta Tung Forest, Quan Ba District, Ha Giang Province" <em>VNU Journal of Science: Natural Sciences and Technology</em> [Online], Volume 34 Number 1 (23 March 2018)