Cita APA (7a ed.)

Hart, H. L. A. (1961). The concept of law (2nd ed.). Oxford university press.

Cita Chicago Style (17a ed.)

Hart, H. L. A. The Concept of Law. 2nd ed. Oxford: Oxford university press, 1961.

Cita MLA (9a ed.)

Hart, H. L. A. The Concept of Law. 2nd ed. Oxford university press, 1961.