1. Maze, T.H., Agarwal, M., & Burchett, G. (2005). Whether Weather Matters to Traffic Demand, Traffic Safety, and Traffic Flow. Center for Transportation Research and Education, Iowa State University. Final General Report.[DOT F 1700.7 (8-72)].
2. FHWA, Road Weather Management Overview, http://ops.fhwa.dot.gov/weather/overview.htm, 2008.
3. Billot, R., El Faouzi, N.-E., Sau, J. & De Vuyst, F. (2008). How Does Rain Affect Traffic Indicators? Empirical Study on a French Interurban Motorway, In Proceedings of the Lakeside Conference. Klagenfurt, Austria.
4. Jung, S. (2010). Modeling Highway Safety and Operational Impacts of Rain, A Ph.D. Dissertation, University of Wisconsin–Madison.
5. Qin, L. & Shao, C. (2003). Traffic Crash Analysis of Ji-Qing Freeway, Journal of Shandong Transportation College, Vol. 11, No. 3, pp. 23-36.