1) Illinoi DOT District 1 Bureau of maintenace: Snow control manual, pp. I-1-V-13, Oct., 1984.
2) Minisrtry of Transportation and Communication, Ontario: Management and control of winter operations, pp. 126, Oct., 1984.
3) 武市靖: 道路の雪氷管理に関する調査研究, 開発論集, 第38号, pp. 23-53, Oct., 1986.
4) Rayer, P. J.: The Meteorological office forecast road surface temperature model, Meteorological Magagine, Vol. 116, pp. 180-190, 1987.
5) Thornes, J. E.: A preliminary performance and benefit analysis of the UK national road ice prediction system, Meteorological Magagine, Vol. 118, pp. 93-99, May, 1989.