Significant changes in preference of illicit drug use in a population of Hanoi, Vietnam—A 6‐year wastewater study (2018–2023). - Hue, Tran Thi Thanh; Ngo, Hieu K. T.; Wang, Zhe; Anh, Nguyen Thi Kieu; Binh, Vu Ngan; Trung, Ngo Quang; Chinh, Pham Quoc; Luong, Hai Thanh; Zheng, Qiuda; Hall, Wayne; Thai, Phong K. (Addiction, 2025)