FamilySearch (https://familysearch.org/ark:/61903/1:1:MZ3G-8YZ), Marita H Duffus in household of Robert C Duffus, Kalamazoo Ward 3, Kalamazoo, Michigan, United States; citing ED 160, sheet 4A, line 20, family 84, NARA microfilm publication T625 (Washington D.C.: National Archives and Records Administration, 1992), roll 775; FHL microfilm 1,820,775.