Phanikumar CV, Maitra B. Willingness-to-pay and preference heterogeneity for rural bus attributes. J Transp Eng A-Syst. 2007 Jan;133(1).
Anderson JJB, Anthony M, Messina M, Garner SC. Effects of phyto-oestrogens on tissues. Nutr Res Rev. 1999 Jun;12(01):75-116.