"United States Census, 1880," index and images, FamilySearch (https://familysearch.org/pal:/MM9.1.1/MW34-N6S : accessed 19 Feb 2014), William Bartels, Grand Haven, Ottawa, Michigan, United States; citing sheet 378C, family 0, NARA microfilm publication T9-0600
"United States Census, 1900," index and images, FamilySearch (https://familysearch.org/pal:/MM9.1.1/MSMT-P4K : accessed 19 Feb 2014), William Bartels, Precinct 1 Grand Rapids city Ward 6, Kent, Michigan, United States; citing sheet , family 7, NARA microfilm publication T623, FHL microfilm 1240722.