Heinrich Zahl and his family are recorded on the 1798 census of Bettinger in Household No. Bt32.
His descendants are recorded on the 1834 census of Bettinger in Households No. 71 & 73.
- 1834 Bettinger Census (Households No. 71, 73).
- 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): Bt32.