Khon, Seyhak, and Udomsak Seenprachawong. 2020. “The Public Demand for a Dengue Fever Vaccine: A Contingent Valuation Survey in Phnom Penh, Cambodia”. International Journal of Economics and Financial Issues 10 (6):129-38. https://mail.econjournals.com/index.php/ijefi/article/view/10426.