Correspondence Among Marxists

I have been (re?-)transcribing various letters in which various points of Marxism are elaborated. This post is an index of what I have so far. I do not know that I will go on much.

• Marx to Engels, 2 April 1958, describes six books he intends to write.
• Marx to Engels, 2 August 1862, sets out the transformation problem and Marx's solution.
• Marx to Engels, 18 June 1867, on the order of presentation in Capital.
• Marx to Engels, 24 August 1867, on the two best points in volume 1 of Capital.
• Marx to Engels, 8 January 1868, on three original points in volume 1 of Capital.
• Marx to Engels, 30 April 1868, outlines the three volumes of Capital, especially the transformation problem.
• Marx to Vera Zasulich, 8 March 1881, on how Russia might not go through the same modes of production as western Europe.
• Engels to J. Bloch, 21 September, 1890, about historical materialism and the relation of the superstructure to the base.
• Engels to Conrad Schmidt, 27 October, 1890, about historical materialism and the relation of the superstructure to the base.
• Engels to Franz Mehring, 14 July 1893, which initiates the concept of false consciousness.
• Engels to Werner Sombart, 11 Marx 1895, on the law of value.
• Antonio Labriola to Georges Sorel, 14 May 1897, in which he describes historical materialism as the philosophy of praxis.

You can see that I am interested in the political economy, and a bit in historical materialism.