"United States Census, 1900," index and images, FamilySearch (https://familysearch.org/pal:/MM9.1.1/MS9P-T44 : accessed 11 March 2015), Ralph Spoolma in household of George Spoolma, Crockery township, Ottawa, Michigan, United States; citing sheet 7A, family 138, NARA microfilm publication T623 (Washington, D.C.: National Archives and Records Administration, n.d.); FHL microfilm 1,240,738.