"Article 2 of Chapter 2 of Division 1". California Streets and Highways Code. Sacramento: California Office of Legislative Counsel. Retrieved February 6, 2019.
Federal Highway Administration (March 25, 2015). National Highway System: California (South)(PDF) (Map). Scale not given. Washington, DC: Federal Highway Administration. Retrieved October 15, 2017.
Natzke, Stefan; Neathery, Mike & Adderly, Kevin (June 20, 2012). "What is the National Highway System?". National Highway System. Washington, DC: Federal Highway Administration. Retrieved July 1, 2012.