"United States Census, 1880," index and images, FamilySearch (https://familysearch.org/ark:/61903/1:1:MZZ2-449 : accessed 14 May 2015), Sarah J Swart in household of Peter Swart, Sidney, Delaware, New York, United States; citing enumeration district 79, sheet 371A, NARA microfilm publication T9 (Washington D.C.: National Archives and Records Administration, n.d.), roll 0823; FHL microfilm 1,254,823.