1. AASHTO, 2001. A Policy on Geometric Design of Highways and Streets, 4th ed., AASHTO.
2. Alaedini, P., Rogness, R.O., 1992. Analysis of fog-related crashes in Ohio. In: Presented at the 71st Annual Meeting of the Transportation Research Board, Washington, DC.
3. Analysis of time headways on Urban roads: case study from Riyadh;Al-Ghamdi;J. Transport. Eng. ASCE,2001
4. Al-Ghamdi, A.S., 2003. Studying the effect of fog on traffic safety in Al-Baha Region. Final Report, Project OM-9-7. King Abdulaziz city of science and technology (KACST), Riyadh, Saudi Arabia.
5. Al-Saif, A., et al., 1990. Investigation of the causes of traffic crashes in Makkah and Eastern regions and their countermeasures. King Abdulaziz City of Science and Technology, Riyadh, Saudi Arabia.