Cita APA (7th ed.)

Ross, R. G. (1970). Obligation: A social theory. University of Michigan Press.

Cita Chicago (17th ed.)

Ross, Ralph Gilbert. Obligation: A Social Theory. Ann Arbor: University of Michigan Press, 1970.

Cita MLA (9th ed.)

Ross, Ralph Gilbert. Obligation: A Social Theory. University of Michigan Press, 1970.