"United States Census, 1940," database with images, FamilySearch (https://familysearch.org/ark:/61903/1:1:K948-5KS : 14 March 2018), Marcus Dugan in household of James Dugan, Ward 2, Santa Ana, Santa Ana Judicial Township, Orange, California, United States; citing enumeration district (ED) 30-84, sheet 61B, line 59, family 358, 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 274. - Marcus Dugan dans le foyer de James Dugan, "United States Census, 1940"
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