United States Census, 1870," database with images, FamilySearch (https://familysearch.org/ark:/61903/1:1:M86P-MTR : 12 April 2016), Isaac Allerton, New York, United States; citing p. 10, family 87, NARA microfilm publication M593 (Washington D.C.: National Archives and Records Administration, n.d.); FHL microfilm 552,406.
New York State Census, 1875," database with images, FamilySearch (https://familysearch.org/ark:/61903/1:1:VTD6-NXY : 30 June 2016), Isaac Allerton, Fenton, Broome, New York, United States; citing p. 5, line 16, State Library, Albany; FHL microfilm 808,830.
United States Census, 1880," database with images, FamilySearch (https://familysearch.org/ark:/61903/1:1:MZZ9-JJ1 : 12 August 2016), Isaac Allerton, Fenton, Broome, New York, United States; citing enumeration district ED 46, sheet 307C, NARA microfilm publication T9 (Washington D.C.: National Archives and Records Administration, n.d.), roll 0810; FHL microfilm 1,254,810.