"United States Census, 1920," index and images, FamilySearch (https://familysearch.org/pal:/MM9.1.1/M4TB-YJD : accessed 7 January 2015), Mary W Wilkinson in household of Harry R Wilkinson, Madison, Morris, New Jersey, United States; citing sheet 14B, family 290, NARA microfilm publication T625, National Archives and Records Administration, Washington D.C.; FHL microfilm 1,821,060.
"United States Census, 1930," index and images, FamilySearch (https://familysearch.org/pal:/MM9.1.1/X4FW-CC1 : accessed 7 January 2015), Mary W Wilkinson in household of Harry R Wilkinson, Madison, Morris, New Jersey, United States; citing enumeration district (ED) 0032, sheet 3B, family 53, line 70, NARA microfilm publication T626, (Washington D.C.: National Archives and Records Administration, 2002), roll 1373; FHL microfilm 2,341,108.
"United States Census, 1940," index and images, FamilySearch (https://familysearch.org/pal:/MM9.1.1/K4RW-F25 : accessed 7 January 2015), Mary Wolf Wilkinson in household of Harry Rockafeller Wilkinson, Ward 1, West Orange, West Orange Town, Essex, New Jersey, United States; citing enumeration district (ED) 7-377, sheet 13A, family 267, NARA digital publication T627 (Washington, D.C.: National Archives and Records Administration, 2012), roll 2341.