Cita APA (7a ed.)

Santayana, G. (1928). Realms of being. Constable and Co..

Cita Chicago Style (17a ed.)

Santayana, George. Realms of Being. London: Constable and Co., 1928.

Cita MLA (9a ed.)

Santayana, George. Realms of Being. Constable and Co., 1928.