(1964). The metaphysical principles of virtue: Part II of the metaphysics of morals. The Bobbs-Merrill.
Chicago-viite (17. p.)The Metaphysical Principles of Virtue: Part II of the Metaphysics of Morals. Indianápolis: The Bobbs-Merrill, 1964.
MLA-viite (9. p.)The Metaphysical Principles of Virtue: Part II of the Metaphysics of Morals. The Bobbs-Merrill, 1964.
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