Wrenn, B. (1988). Instructor's manual: marketing management: Analysis, planning, implementation, and control (6th ed.). Prentice-Hall.
Cita Chicago (17th ed.)Wrenn, Bruce. Instructor's Manual: Marketing Management: Analysis, Planning, Implementation, and Control. 6th ed. Englewood Cliffs, N.J: Prentice-Hall, 1988.
Cita MLA (9th ed.)Wrenn, Bruce. Instructor's Manual: Marketing Management: Analysis, Planning, Implementation, and Control. 6th ed. Prentice-Hall, 1988.
Atenció: Aquestes cites poden no estar 100% correctes.