Michigan Death Certificates, 1921-1952," database, FamilySearch (https://familysearch.org/ark:/61903/1:1:KF3P-BNG : 12 December 2014), Joseph Szyszko, 08 Apr 1951; citing Grand Rapids, Kent, Michigan, United States, Division for Vital Records and Health Statistics, Lansing; FHL microfilm 1,972,832.
"Michigan Obituaries, 1820-2006," database with images, FamilySearch (https://familysearch.org/ark:/61903/1:1:QVPK-FQLJ : 11 June 2015), Mr Joseph Szyszko, 1951; citing various offices and archives, Michigan.