In 1797, Johann Heinrich Dettloff moved from Volmer to Semenovka. Georg Heinrich [sic] Dettloff from Volmer and his family are recorded on the 1798 census of Semenovka in Household No. Se16.
- 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): Se16, Mv2948.