"United States Census, 1940," database with images, FamilySearch (
https://familysearch.org/ark:/61903/1:1:K4VW-SYH : accessed 27 December 2015), Wilbur Smulovitch in household of Jacob Vanpraag, Ward 17, Boston, Boston City, Suffolk, Massachusetts, United States; citing enumeration district (ED) 15-589, sheet 4A, family 65, NARA digital publication T627 (Washington, D.C.: National Archives and Records Administration, 2012), roll 1676.