Mansfield CA, Johnson FR, Van Houtven GL. The missing piece: valuing averting behavior for children's ozone exposures. Resour Energy Econ. 2006 Aug;28(3):215-28.
Phanikumar CV, Maitra B. Modeling willingness-to-pay values for rural bus attributes under different trip purposes. JTRF. 2006;45(2):31-44. doi: 10.22004/ag.econ.206787