"United States Census, 1930," database with images, FamilySearch (https://familysearch.org/ark:/61903/1:1:X7M7-LHF : accessed 4 August 2015), Tillie Jonkers in household of Jennie Vandertuuk, Holland, Ottawa, Michigan, United States; citing enumeration district (ED) 0018, sheet 19A, family 486, line 42, NARA microfilm publication T626 (Washington D.C.: National Archives and Records Administration, 2002), roll 1024; FHL microfilm 2,340,759.