encyclopedia of codenames of World War II. Routledge. p. 109. ISBN 0710207182 ^ Curtis, Glenn E. (1992). Yugoslavia: A Country Study. Library of Congress
Bombing by the US-led NATO of the Chinese Embassy in the Federal Yugoslavia”. Ministry of Foreign Affairs of the People's Republic of China (November 17, 2001)
German and English" (PDF). Berlin, Germany: Memorial for the Victims of National Socialist ›Euthanasia‹ Killings. 2018. "Euthanasia Program" (PDF). Yad Vashem