Urbano. The Philosophical Life. The Catholic University of America Press.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रUrbano. The Philosophical Life. The Catholic University of America Press.
एमएलए (9वां संस्करण) प्रशस्ति पत्रUrbano. The Philosophical Life. The Catholic University of America Press.
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