PFEIFFER J W. (1980). 1980 ANNUAL HANDBOOK FOR GROUP FACILITATORS. HUMAN REL. TRAINING.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रPFEIFFER J W. 1980 ANNUAL HANDBOOK FOR GROUP FACILITATORS. CALIFORNIA: HUMAN REL. TRAINING, 1980.
एमएलए (9वां संस्करण) प्रशस्ति पत्रPFEIFFER J W. 1980 ANNUAL HANDBOOK FOR GROUP FACILITATORS. HUMAN REL. TRAINING, 1980.
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