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
Nicholls TJ, Green KL, Cook DJ, Rogers DJ, Wolowacz SE, Smart JD. An investigation of lectins for use in ophthalmic drug delivery. Int J Pharm. 1996;138(2):175-83.