"United States Census, 1940," index and images, FamilySearch (https://familysearch.org/pal:/MM9.1.1/K7VX-CFQ : accessed 22 February 2015), Helen Andringa in household of Grace Andringa, Ward 3, Sparta, Sparta City, Monroe, Wisconsin, United States; citing enumeration district (ED) 41-31, sheet 7B, family 145, NARA digital publication T627 (Washington, D.C.: National Archives and Records Administration, 2012), roll 4505.