1. Artusa, A., 2012. U.S. Drought Monitor. September 25, 2012. 〈http://droughtmonitor.unl.edu/data/pngs/20120925/20120925_conus_trd.png〉.
2. Community Collaborative Rain, Hail, and Snow Network, 2015. 〈http://www.cocorahs.org/Content.aspx?page=aboutus〉.
3. Impacts of California's ongoing drought: agriculture;Cooley;Pac. Inst.,2015
4. Department of Homeland Security, 2014. National Preparedness Report, pp. 74.
5. National Disaster Recovery Framework: Strengthening Disaster Recover for the Nation;Environmental Prediction Agency (EPA),2011