THÀNH, Trần Đức.
 Quantifying the Tourism Value of Halong bay.
<strong>VNU Journal of Science: Natural Sciences and Technology</strong>, [S.l.], v. 18, n. 4, dec. 2002.
ISSN 2588-1140.
Available at: &lt;<a href="https://js.vnu.edu.vn/NST/article/view/3153" target="_new">https://js.vnu.edu.vn/NST/article/view/3153</a>&gt;. Date accessed: 09 may 2024.