1. Global status report on road safety: time for action. Geneva, World Health Organization, 2009. http://www.who.int/violence_injury_prevention/road_safety_status/2009
2. World health statistics 2008. Geneva, World Health Organization, 2008. http://www.who.int/whosis/whostat/2008/en/index.htm
3. Compliance of proper safety helmet usage in motorcyclists;Kulanthayan;Med J Malaysia,2000