6Wilhelmi O V, Wilhite D A. Assessing Vulnerability to Agricultural Drought: A Nebraska Case Study. Natural Hazards[J]. 2002, 25(1): 37-58.
7Fontaine M M, Steinemann A C, ASCE M. Assessing Vulnerability to Natural Hazards: Impact-Based Method and Application to Drought in Washington State[J]. Natural Hazards Review, 2009, 10(1): 11 - 18.
8Simelton E, Fraser E D G, Terrnansen M, et al. Typologies of crop-drought vulnerability: an empirical analysis of the socio-economic factors that influence the sensitivity and resilience to drought of three major food crops in China (1961-2001)[J]. Environmental Science and Policy, 2009, 12(4): 438-452.
9Allen R G, Perreira L S, Raes D, et al. Crop evapotranspiration: Guidelines for computing crop water requirement [R]. Rome: FAO, 1998.
