"United States Census, 1930," index and images, FamilySearch (https://familysearch.org/pal:/MM9.1.1/XQBX-QTR : accessed 24 Aug 2013), Dina Schipper in entry for William M Schipper, 1930.
"United States World War II Draft Registration Cards, 1942," index and images, FamilySearch (https://familysearch.org/pal:/MM9.1.1/J4SN-9YS : accessed 24 Aug 2013), Willem Myndert Schipper, 1942. Place of residence 1330 Myrtle NW, Grand Rapids,