Washington State Legislature (1937). Session Laws of the State of Washington (1937 ed.). Olympia: Washington State Legislature. p. 1008. Retrieved January 6, 2013.
Washington State Legislature (1943). Session Laws of the State of Washington (1943 ed.). Olympia: Washington State Legislature. pp. 716, 723–724. Retrieved January 6, 2013.
Washington State Legislature (1961). Session Laws of the State of Washington (1961 ed.). Olympia: Washington State Legislature. pp. 521, 2650. Retrieved January 6, 2013.