"Population of Metropolitan Districts". Abstract of the Thirteenth Census, 1910(PDF) (Report). United States Census Bureau. 1913. pp. 61–62. Retrieved January 26, 2024.
"Metropolitan Districts"(PDF). Fifteenth Census of the United States: 1930 (Report). United States Census Bureau. 1932. p. 214. Retrieved January 26, 2024.
Washington State K–12 School Districts(PDF) (Map). 1 inch = 25 miles. Washington State Office of Superintendent of Public Instruction. February 10, 2020. Retrieved February 26, 2024.
Washington State Department of Transportation (2022). General Highway Map, State of Washington(PDF) (Map). Olympia: Washington State Department of Transportation. Puget Sound inset. Retrieved February 13, 2024.{{cite map}}: CS1 maint: url-status (link)
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 February 21, 2024.
"2018 Corridor Capacity Report"(PDF). Washington State Department of Transportation. November 2018. pp. 12, 31–32. Retrieved February 13, 2024.
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 February 13, 2024.
"Ramp meters". Washington State Department of Transportation. Retrieved February 13, 2024.
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 February 21, 2024.