"South Dakota, Department of Health, Index to Births 1843-1914 and Marriages 1950-2016," database, FamilySearch (https://familysearch.org/ark:/61903/1:1:QKD8-6FZM : 2 September 2015), Emil Mehlhaff, 13 Aug 1893; citing Birth, Mcpherson, South Dakota, United States, South Dakota Department of Health, Pierre.
Find A Grave, database and images (https://new.findagrave.com : accessed 05 November 2017), memorial page for Emil Mehlhaff (13 Aug 1893–17 May 1968), Find A Grave Memorial no. 128024905, citing Eureka City Cemetery, Eureka, McPherson County, South Dakota, USA ; Maintained by Donald Schmidt (contributor 47813253). Find A Grave: Memorial #128024905 does not include a gravestone picture.
Named in wife's obituary which provided his death date and their marriage date. - "United States, Obituaries, American Historical Society of Germans from Russia, 1899-2012," database with images, FamilySearch (https://familysearch.org/ark:/61903/1:1:QVS3-3VF7 : 1 July 2016), Emil Mehlhaff in entry for Mrs Katherine Or Katie Hieb Mehlhaff, 21 Dec 1991; citing Obituary, in "Northwest Blade"; American Historical Society of Germans from Russia, Lincoln.