Giap, N. H., P. Janekarnkij, and O. Nabangchang. “Enhancing the Recreational Benefits of Trang An Landscape Complex for Vietnamese Visitors”. SOUTHEAST ASIAN JOURNAL OF ECONOMICS, vol. 7, no. 1, Mar. 2019, pp. 41-70, https://so05.tci-thaijo.org/index.php/saje/article/view/178443.