Johannes Alt and his family are recorded on the 1798 census of Rosenheim in Household No. Rm10.
The death of Johannes Alt in 1819 is recorded on the 1834 census of Rosenheim in Household No. 8.
- 1834 Rosenheim Census (Household No. 8).
- 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): Rm10.