"United States Census, 1930," database with images, FamilySearch (https://familysearch.org/ark:/61903/1:1:XC39-YHQ : accessed 3 June 2021), Hatsum Korekiyo in household of Tsuneta Korekiyo, Christopher, King, Washington, United States; citing enumeration district (ED) ED 260, sheet 8B, line 53, family 179, NARA microfilm publication T626 (Washington D.C.: National Archives and Records Administration, 2002), roll 2489; FHL microfilm 2,342,223.
"United States Census, 1940," database with images, FamilySearch (https://www.familysearch.org/ark:/61903/1:1:K99P-8L6 : 6 January 2021), Hatsumi Korekiyo in household of Tsuneta Korekiyo, Christopher Election Precinct, King, Washington, United States; citing enumeration district (ED) 17-48, sheet 13A, line 38, family 261, Sixteenth Census of the United States, 1940, NARA digital publication T627. Records of the Bureau of the Census, 1790 - 2007, RG 29. Washington, D.C.: National Archives and Records Administration, 2012, roll 4343.