Thi N, Hoang O, Thi To H. Air quality improvement estimation using contingent valuation method in HoChiMinh City. VNUHCM Journal of Science and Technology Development [Internet]. 31Dec.2014 [cited 26Apr.2025];17(4):5-2. Available from: http://stdj.scienceandtechnology.com.vn/index.php/stdj/article/view/1533