Martorella, P. H. (1976). Elementary social studies as a learning system. Harper & Row.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रMartorella, Peter H. Elementary Social Studies as a Learning System. New York: Harper & Row, 1976.
एमएलए (9वां संस्करण) प्रशस्ति पत्रMartorella, Peter H. Elementary Social Studies as a Learning System. Harper & Row, 1976.
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