Eckhardt, K. W. (1977). Instructor's manual for social research methods: Perspective, theory, and analysis. Random House, Inc.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रEckhardt, Kenneth W. Instructor's Manual for Social Research Methods: Perspective, Theory, and Analysis. New York: Random House, Inc, 1977.
एमएलए (9वां संस्करण) प्रशस्ति पत्रEckhardt, Kenneth W. Instructor's Manual for Social Research Methods: Perspective, Theory, and Analysis. Random House, Inc, 1977.
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