Não informado. (1940). Main Currents in Modern Thought. Center for Integrated Education.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रNão informado. Main Currents in Modern Thought. New York: Center for Integrated Education, 1940.
एमएलए (8वां संस्करण) प्रशस्ति पत्रNão informado. Main Currents in Modern Thought. Center for Integrated Education, 1940.
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