"United States Census, 1850," database with images, FamilySearch (https://familysearch.org/ark:/61903/1:1:MCY3-RQD : accessed 19 July 2015), Freer Swart, Middletown, Delaware, New York, United States; citing family , NARA microfilm publication M432 (Washington, D.C.: National Archives and Records Administration, n.d.).