Pfeiffer, J. W. (1989). The Encyclopedia of group activities: 150 practical designs for successful facilitating. University Associates.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रPfeiffer, J. William. The Encyclopedia of Group Activities: 150 Practical Designs for Successful Facilitating. San Diego, Calif.: University Associates, 1989.
एमएलए (8वां संस्करण) प्रशस्ति पत्रPfeiffer, J. William. The Encyclopedia of Group Activities: 150 Practical Designs for Successful Facilitating. University Associates, 1989.
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