Karl Dups, a farmer, his wife Margaretha, and children (Johannes, age 16; Regina, age 11) are recorded on the 1767 census of Reinwald in Household No. 36. They had settled there on 14 July 1766.
Karl Dups, his daughter Regina, and her family are recorded on the 1798 census of Reinwald in Household No. Rw32.
The 1798 census of Rosenheim records Johannes Dubs in Household No. Rm09 and Adam Dubs in Household No. Rm16.
The 1767 census records that Karl Dubs came from the German village of Heilbronn.
- 1834 Rosenheim Census (Households No. 1 & 18).
- Mai, Brent Alan. 1798 Census of the German Colonies along the Volga: Economy, Population, and Agriculture (Lincoln, NE: American Historical Society of Germans from Russia, 1999): Rw32, Rm09, Rm16.
- Pleve, Igor. Einwanderung in das Wolgagebiet, 1764-1767 Band 4 (Göttingen: Göttinger Arbeitskreis, 2008): 39.