1. Safety in automated transportation tunnels;Abdul Salam,2007
2. ANSI Z535.1-2006 - R2011. (2011). Safety Colors. American National Standards Institute, Inc.
3. APWA (American Public Works Association). (1999). Color Code and Marking Guidelines, 4/1999.
4. Doing our best: Optimization and the management of risk;Ben-Haim;Risk Analysis,2012
5. Sustainable development of urban underground space for utilities;Cano-Hurtado;Tunnelling and Underground Space Technology,1999