"United States Census, 1910," database with images, FamilySearch (https://familysearch.org/ark:/61903/1:1:M2G6-14V), Hellen Vallentyne in household of Geo Vallentyne, Minneapolis Ward 13, Hennepin, Minnesota, United States; citing enumeration district (ED) ED 202, sheet 3B, family 69, NARA microfilm publication T624 (Washington D.C.: National Archives and Records Administration, 1982), roll 706; FHL microfilm 1,374,719.
"United States Census, 1920," database with images, FamilySearch (https://familysearch.org/ark:/61903/1:1:MWY2-CDH), Helen Valentine in household of George G Valentine, Minneapolis Ward 8, Hennepin, Minnesota, United States; citing ED 135, sheet 5A, line 14, family 98, NARA microfilm publication T625 (Washington D.C.: National Archives and Records Administration, 1992), roll 835; FHL microfilm 1,820,835.
"United States Census, 1930," database with images, FamilySearch (https://familysearch.org/ark:/61903/1:1:XCDS-GXJ), Helen J Anderson in household of Carl J Anderson, Alhambra, Los Angeles, California, United States; citing enumeration district (ED) ED 1419, sheet 13A, line 38, family 382, NARA microfilm publication T626 (Washington D.C.: National Archives and Records Administration, 2002), roll 173; FHL microfilm 2,339,908.
"California Death Index, 1940-1997," database, FamilySearch (https://familysearch.org/ark:/61903/1:1:VP6M-6KS), Helen Joyce Anderson, 15 Apr 1993; Department of Public Health Services, Sacramento.