Kikkas, Toivo. “Surveillance Reports of National Units of the Red Army Political Departments in 1918–1920”. Journal of the University of Latvia. History | Latvijas Universitātes Žurnāls. Vēsture, no. 16 (December 22, 2023): 39–55. Accessed July 3, 2024. https://journal.lu.lv/luzv/article/view/635.