Adamczewski, P. (2020). Jusuf-bek Umaszew and the importance of the Caucasus for Polish intelligence services during World War II in view of documents kept in Polish archives in London. Studia Z Dziejów Rosji I Europy Środkowo-Wschodniej, 55(3), 57–73. https://doi.org/10.12775/SDR.2020.EN5.03