Allen, R. Y., & Spohn, R. F. W. (1987). Selling Dynamics. McGraw-Hill.
Chicago Edition CitationAllen, Robert Y., i Robert F Wilson Spohn. Selling Dynamics. New York: McGraw-Hill, 1987.
Cita MLAAllen, Robert Y., i Robert F Wilson Spohn. Selling Dynamics. McGraw-Hill, 1987.
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