Werth, Nicholas (1999). “A State against Its People: Violence, Repression, and Terror in the Soviet Union”. In Courtois, Stéphane (ed.). The Black Book of Communism: Crimes, Terror, Repression. Translated by Mark Kraemer; Jonathan Murphy (illustrated hardcover ed.). Cambridge, Massachusetts: Harvard University Press. p. 164. ISBN 9780674076082. Retrieved 2 December 2021 – via Google Books.
There are dozens of sources listed on the bottom, one possibly questionable source means the entire thing is made up?