Liu X, Miao H, Behrman JR, Hannum E, Liang Z, Zhao Q. The Asian Games, air pollution and birth outcomes in South China: an instrumental variable approach. Econ Hum Biol. 2022 Jan;44:101078. doi: 10.1016/j.ehb.2021.101078
Phanikumar CV, Maitra B. Willingness-to-pay and preference heterogeneity for rural bus attributes. J Transp Eng A-Syst. 2007 Jan;133(1).