"United States Census, 1940," database with images, FamilySearch (https://familysearch.org/ark:/61903/1:1:KQH2-6YP : 14 March 2018), Charles F Hirtzel in household of Charles Hirtzel, North East Township, Erie, Pennsylvania, United States; citing enumeration district (ED) 25-44, sheet 8B, line 72, family 184, 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 3501. - Charles F Hirtzel dans le foyer de Charles Hirtzel, "United States Census, 1940"
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