"United States Census, 1930," database with images, FamilySearch (https://familysearch.org/ark:/61903/1:1:X385-B7P : accessed 26 February 2017), Carl O Dokken, Langhei, Pope, Minnesota, United States; citing enumeration district (ED) ED 14, sheet 2B, line 63, family 38, NARA microfilm publication T626 (Washington D.C.: National Archives and Records Administration, 2002), roll 1113; FHL microfilm 2,340,848.
"United States Census, 1940," database with images, FamilySearch (https://familysearch.org/ark:/61903/1:1:KSLM-3TM : accessed 26 February 2017), Carl O Dokken, Benson, Benson City, Swift, Minnesota, United States; citing enumeration district (ED) 76-3A, sheet 14B, line 44, family 318, 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 1963.