Works and correspondence of David Ricardo : edited by Piero Sraffa ; with the collaboration of M.H. Dobb. Vol. 6 / Ricardo, David, 1772-1823. Dobb, Maurice, 1900-1976. Sraffa, Piero. Royal Economic Society (Great Britain) Malthus, T. R. (Thomas Robert), 1766-1834. Principles of political economy. Economics. 923.3 RIW Includes bibliographical references. Cambridge : At the University Press for the Royal Economic Society, 1951-1952 (1973 printing). 1951-1952 1973 Text 11 v. : eng