There are many translations and editions of Marx's best-known works and of his and Engels's selected correspondence. See the Collected Works of Marx and Engels (40 vol., 1975–83). The standard biography of Marx is that by F. Mehring (tr. 1935); other notable works include those by O. Rühle (tr. 1929), E. H. Carr (1938), C. J. S. Sprigge (1938), K. Korsch (1939), and I. Berlin (4d ed. 1978). Recent biographies include those by R. Payne (1968), D. McLellan (1973), P. Singer (1980), A. Wood (1985), and F. Wheen (2000). See also bibliography under Marxism.