Cita APA (7a ed.)

Spencer, H. (1978). The Principles of Ethics: In Two Volumes. Liberty Fund.

Cita Chicago Style (17a ed.)

Spencer, Herbert. The Principles of Ethics: In Two Volumes. Indianapolis [Indiana]: Liberty Fund, 1978.

Cita MLA (8a ed.)

Spencer, Herbert. The Principles of Ethics: In Two Volumes. Liberty Fund, 1978.