Levine, M. (1994). Effective problem solving (2nd edition.). Prentice-Hall of India.
Čikaški stil citiranjaLevine, Marvin. Effective Problem Solving. 2nd edition. Englewood Cliffs: Prentice-Hall of India, 1994.
MLA način citiranjaLevine, Marvin. Effective Problem Solving. 2nd edition. Prentice-Hall of India, 1994.
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