Report of Soviet military attaché in Germany V. Tupikov to Chief of the Intelligence Directorate of the General Staff of the Red Army F. Golikov about the inevitability of a German attack against the USSR in 1941 (with attached information about the deployment of the German Army as of 25 April 1941)

25 April 1941
Central Archive of the Ministry of Defence of the Russian Federation
Coll. 23, ser. 7277, fold. 1, ff. 140–152.