Kaufman, R. A. (1976). Identifying and solving problems: A system approach. University Associates.
Chicago Style aipamenaKaufman, Roger A. Identifying and Solving Problems: A System Approach. La Jolla, Calif.: University Associates, 1976.
MLA aipamenaKaufman, Roger A. Identifying and Solving Problems: A System Approach. University Associates, 1976.
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