In the Soviet CW of Lenin see volume 45, pg. 190 for the Letter to Kursky (not Kutsky) who was Peoples Commissar for Justice, in the early Soviet period, before being appointed Amb. to Italy.
In the English CW that is vol. 33.
Letter quoted in Medvedev, "Let History Judge, " 2nd ed. pg. 665. Also In The GULAG Archipelago, vol. 1, pg. 353. As well in Dmitry Volganov vol. on Lenin, Trotsky, Stalin, Khruschev.
-- Michael Pugliese