Frieling, R. The art of participation: 1950 to now.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रFrieling, Rudolf. The Art of Participation: 1950 to Now.
एमएलए (8वां संस्करण) प्रशस्ति पत्रFrieling, Rudolf. The Art of Participation: 1950 to Now.
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