Madrid. Alberto Corazón, Editor, 1971. Communication 9. Cover, 227 pages.- "The dialectic of the abstract and the concrete in Marx's Capital", by E. Ilienkov.- "Key to historical dialectics", by G. della Volpe.- "The concrete-abstract-concrete circle", by C. Luporini.- Theory and praxis, by M. Rossi.- "The individual and history", by K. Kosik. Publisher's hardback.
