Ingram, T. N. (2009). Professional selling: A trust-based approach (4th ed.). Cengage Learning Asia.
Citazione stile Chigago Style (17a edizione)Ingram, Thomas N. Professional Selling: A Trust-based Approach. 4th ed. Pasig City: Cengage Learning Asia, 2009.
Citatione MLA (9a ed.)Ingram, Thomas N. Professional Selling: A Trust-based Approach. 4th ed. Cengage Learning Asia, 2009.
Attenzione: Queste citazioni potrebbero non essere precise al 100%.