Santayana, G. (1928). The realm of essence: Book first of Realms of being. Constable.
Chicago-viite (17. p.)Santayana, George. The Realm of Essence: Book First of Realms of Being. London: Constable, 1928.
MLA-viite (8. p.)Santayana, George. The Realm of Essence: Book First of Realms of Being. Constable, 1928.
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