1. Kierkegaard, Soren. 1941. Concluding unscientific postscript (trans: Swenson, David F. and Walter). Princeton: Princeton University Press.
2. Kierkegaard, Soren. 1962. The present age (trans: Dru, Alexander). New York: Harper and Row.
3. Marx, Karl. 1963. Critique of Hegel’s dialectic and general philosophy. In Karl Marx: Early writings, trans. and ed. T.B. Bottomore. New York: McGraw-Hill.
4. Petrovic, Gajo. 1965. Man and freedom. In Socialist humanism, ed. Erich Fromm. Garden City: Doubleday.
5. Petrovic, Gajo. 1963. Needs, production, and division of labor. In Karl Marx: Early writings, trans. and ed. T.B. Bottomore. New York: McGraw-Hill.