Watson V, Ryan M. Exploring preference anomalies in double bounded contingent valuation. J Health Econ. 2007 May 1;26(3):463-82. doi: 10.1016/j.jhealeco.2006.10.009
Yang J, Bogerd HP, Wang PJ, Page DC, Cullen BR. Two closely related human nuclear export factors utilize entirely distinct export pathways. Mol Cell. 2001 Aug;8(2):397-406.