APA (7th ed.) Citation

Locke, J., Hume, D., Rousseau, J., & Barker, E. (1971). Social contract. Oxford University Press.

Chicago Style (17th ed.) Citation

Locke, John, David Hume, Jean-Jacques Rousseau, and Ernest Barker. Social Contract. London [etc.]: Oxford University Press, 1971.

MLA (9th ed.) Citation

Locke, John, et al. Social Contract. Oxford University Press, 1971.