"United States Census, 1850," index and images, FamilySearch (https://familysearch.org/ark:/61903/1:1:MC1W-4M7 : accessed 6 May 2015), William H Swart, Oneonta, Otsego, New York, United States; citing family 680, NARA microfilm publication M432 (Washington, D.C.: National Archives and Records Administration, n.d.).