• U.S. Government Accountability Office, Highway Public- Private Partnerships: More Rigorous Up-Front Analysis Could Better Secure Potential Benefits and Protect the Public Interest, Report No. GAO-08-44, http://www.%20gao.gov/new.items/d0844.pdf
• Reason Foundation, "Building for the Future: Easing California's Transportation Crisis with Tolls and Public- Private Partnerships," Policy Study No. 324, http://www.reason.org/ps324.pdf