"United States Census, 1940," index and images, FamilySearch (https://familysearch.org/pal:/MM9.1.1/K99P-PXK : accessed 25 May 2013), Thomas Roorda, Cherry Valley Election Precinct, King, Washington, United States; citing enumeration district (ED) 17-47, sheet 2A, family 29, NARA digital publication T627, roll 4343.