"Wisconsin, County Marriages, 1836-1911," database, FamilySearch (https://familysearch.org/ark:/61903/1:1:XR2N-L8B : 3 June 2016), Raphael Katz and Caroline Helene Marks, 20 Jul 1874; citing , City Of City Of Fond Du Lac, Wisconsin, United States, Wisconsin Historical Society, Madison; FHL microfilm 1,266,976.
"Wisconsin, Death Records, 1867-1907," database, FamilySearch (https://familysearch.org/ark:/61903/1:1:XLWX-SY1 : 4 December 2014), R. Katz, 1902; citing Death, Fond du Lac, Fond du Lac, Wisconsin, Wisconsin State Historical Society, Madison; FHL microfilm 1,310,184.