↑ "United States Census, 1900," database with images, FamilySearch (https://familysearch.org/ark:/61903/1:1:MSPQ-SN6 : 22 January 2015), Eva Vandermark in household of Soloman Vandermark, Mt. Pleasant Township, Westchester, New York, United States; citing sheet 5A, family 42, NARA microfilm publication T623 (Washington, D.C.: National Archives and Records Administration, n.d.); FHL microfilm 1,241,175.
↑ "United States Census, 1910," database with images, FamilySearch (https://familysearch.org/ark:/61903/1:1:M54T-BSZ : 29 October 2015), Eva Vande Mark in household of Saul Vande Mark, Wawarsing, Ulster, New York, United States; citing enumeration district (ED) ED 182, sheet 4A, NARA microfilm publication T624 (Washington, D.C.: National Archives and Records Administration, n.d.); FHL microfilm 1,375,099.
↑ "United States Census, 1920," database with images, FamilySearch (https://familysearch.org/ark:/61903/1:1:MVS5-53C : 14 December 2015), Derrick Irwin in household of Saul Vandemark, Wawarsing, Ulster, New York, United States; citing sheet 3A, NARA microfilm publication T625 (Washington D.C.: National Archives and Records Administration, n.d.); FHL microfilm 1,821,270.
↑ "United States Census, 1940," database with images, FamilySearch (https://familysearch.org/ark:/61903/1:1:KQ3L-GM9 : accessed 11 September 2016), Derrick Irwin, Wawarsing Town, Ulster, New York, United States; citing enumeration district (ED) 56-90, sheet 10B, family 235, 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 2796.
↑ "New York Marriages, 1686-1980," database, FamilySearch (https://familysearch.org/ark:/61903/1:1:F6S8-1LB : 12 December 2014), Derrick E. Irwin and Eva Vandermark, 11 Dec 1912; citing reference 583; FHL microfilm 842,643.
↑ "United States Social Security Death Index," database, FamilySearch (https://familysearch.org/ark:/61903/1:1:VS6R-MMX : 20 May 2014), Eva Irwin, Jan 1975; citing U.S. Social Security Administration, Death Master File, database (Alexandria, Virginia: National Technical Information Service, ongoing).