"December 2006"--T.p.; Research conducted by Public Agenda and Doble Research; principal authors Ana Maria Arumi and John Doble.; Harvested from the web on 3/22/07
"Updated July 30, 2007."; Title from PDF title screen.; Includes bibliographical references.; Text document in PDF format.; Harvested from the web on 12/14/07
Performed in cooperation with the California Dept. of Transportation and the Federal Highway Administration.; "November 2005."; Harvested from the web on 9/28/07