Levin, R. I., Travis, G., & Branch, J. (1981). The executive's illustrated primer of long-range planning. Prentice-Hall.
Chicago Style aipamenaLevin, Richard I., Ginger Travis, and John Branch. The Executive's Illustrated Primer of Long-range Planning. Englewood Cliffs, N.J: Prentice-Hall, 1981.
MLA aipamenaLevin, Richard I., et al. The Executive's Illustrated Primer of Long-range Planning. Prentice-Hall, 1981.
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