Family tree▼
"United States Census, 1880," index and images, FamilySearch (https://familysearch.org/pal:/MM9.1.1/MW3H-MJR : accessed 29 May 2013), Gerrit Derks, 1880.
"United States Census, 1870," index and images, FamilySearch (https://familysearch.org/pal:/MM9.1.1/MHC6-SYQ : accessed 29 May 2013), Hermina Dirks in entry for Gerrets Dirks, .