U.S. Department of Transportation
Federal Highway Administration
1200 New Jersey Avenue, SE
Washington, DC 20590
Guidelines and Training for Road Safety Audits", Transportation Safety Planning newsletter: January 2007 issue; page 3.
Safety Check, by Louisa Ward and Margaret Gibbs, Roads & Bridges magazine, June 2006
Being Proactive, by Chris Brown and Tricia Williams, Roads & Bridges magazine, June 2006