Schiffman, S. (2008). The 25 sales habits of highly successful salespeople (3rd ed.). Adams Media.
Cita Chicago (17th ed.)Schiffman, Stephan. The 25 Sales Habits of Highly Successful Salespeople. 3rd ed. Avon, Mass.: Adams Media, 2008.
Cita MLA (9th ed.)Schiffman, Stephan. The 25 Sales Habits of Highly Successful Salespeople. 3rd ed. Adams Media, 2008.
Atenció: Aquestes cites poden no estar 100% correctes.