STALIN on the Comintern -- speeches and texts http://ciml.250x.com/archive/stalin/english/stalin_on_the_comintern_collection_of_speeches_and_texts.html
Economic Manuscripts: Capital Vol. I - Chapter Thirty Two http://hiaw.org/defcon6/works/1867-c1/ch32.html
Letters: Engels To George Julian Harney Genoa, 5 October 1849 https://marxistleninists.org/M&E/1849/letters/49_10_05.htm
Lenin: The Dying Autocracy and New Organs of Popular Rule https://www.marxists.org/archive/lenin/works/1905/nov/23.htm