[B437] Overlijden Gradus Nijenhuis, Utica, 1911, in: New York State, Department of Health (Albany, New York, USA), Death Index 1911, pagina 673, Certificate nr. 52986 (Gerardus Neyenhouse); FamilySearch (Salt Lake City, Utah, USA), "New York, State Death Index, 1880-1956", online database (met online afbeeldingen van Reclaim The Records, Mill Valley, California, USA),
https://www.familysearch.org/ark:/61903/1:1:QGR1-233W (geraadpleegd 13-01-2022).