1. Status of the nations highways, bridges, and transit: Conditions and performance, report to congress;Administration;Federal Highway Administration (FHWA), Tech Rep,2008
2. ASCE 2009 Report Card for America's Infrastructure Technical report, American Society of Civil Engineers http://www.infrastructurereportcard.org 2009
3. Multiple complementary nondestructive evaluation technologies for condition assessment of concrete bridge decks;Gucunski;Transp Res Rec,2010
4. Wikipedia I-35w mississippi river bridge http://en.wikipedia.org/wiki/I-35W_Mississippi_River_bridge 2007
5. Urbansplatter Washington bridge collapse is a wakeup call http://www.urbansplatter.com/washington-bridge-collapse-is-a-wake-up-call/