"Minnesota Marriages, 1849-1950 ," database, FamilySearch (https://familysearch.org/ark:/61903/1:1:FDXP-5TG : accessed 25 August 2015), Jacob Tammell and Clara Doornink, 30 Nov 1871; citing FHL microfilm 1,316,804.
"Minnesota State Census, 1875," database with images, FamilySearch (https://familysearch.org/ark:/61903/1:1:MKND-PBN : accessed 27 August 2015), Jacob Tammel, Forestville, Fillmore, Minnesota; citing p. 386, line 76, volume Fillmore County (Amherst-Holt), State Library and Records Service, St.Paul; FHL microfilm 0565719.