Heinrich Thomas, an ore miner (Erzbergbauarbeiter), his wife Anna, and her children (Nikolaus Kohl, age 14; Herbert Kohl, age 12) are recorded on the 1767 census of Katharinenstadt in Household No. 87. They had settled there on 27 August 1766
The 1767 census records that Heinrich Thomas came from the [Dutch] village of Amersfoort.
- Pleve, Igor. Einwanderung in das Wolgagebiet, 1764-1767 Band 2 (Göttingen: Göttinger Arbeitskreis, 2001): 295.