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
Fenton M, Huang H, Hong Y, Hawe E, Kurz DJ, Erusalimsky JD. Early atherogenesis in senescence-accelerated mice. Exp Gerontol. 2004;39(1):115-22.