^Lynne Viola (2007). The Unknown Gulag: The Lost World of Stalin's Special Settlements. Oxford University Press (2007). p. 126f. ISBN 978-0-19-518769-4.
^ abcdNikolai Tolstoy (1982). Stalin's Secret War. Holt, Rinehart and Winston (1981). p. 357. ISBN 0-03-047266-0.