Washington State Department of Transportation (2014). Washington State Highways, 2014–2015(PDF) (Map). 1:842,000. Olympia: Washington State Department of Transportation. Puget Sound inset. Retrieved June 21, 2020.
2016 Annual Traffic Report(PDF) (Report). Washington State Department of Transportation. 2017. pp. 205–206. Archived from the original(PDF) on November 9, 2020. Retrieved June 21, 2020.
"Chapter 3: Highways"(PDF). Session Laws of the State of Washington, 1963 extraordinary session. Washington State Legislature. April 6, 1963. p. 1299. Retrieved February 25, 2021.
web.archive.org
Washington State Department of Transportation (2014). Washington State Highways, 2014–2015(PDF) (Map). 1:842,000. Olympia: Washington State Department of Transportation. Puget Sound inset. Retrieved June 21, 2020.
2016 Annual Traffic Report(PDF) (Report). Washington State Department of Transportation. 2017. pp. 205–206. Archived from the original(PDF) on November 9, 2020. Retrieved June 21, 2020.
Cameron, David A.; LeWarne, Charles P.; May, M. Allan; O'Donnell, Jack C.; O'Donnell, Lawrence E. (2005). Snohomish County: An Illustrated History. Index, Washington: Kelcema Books LLC. p. 31. ISBN978-0-9766700-0-1. OCLC62728798.