Peelen, E. (2005). Customer relationship management. Pearson.
Cita Chicago (17th ed.)Peelen, Ed. Customer Relationship Management. New Delhi: Pearson, 2005.
Cita MLA (9th ed.)Peelen, Ed. Customer Relationship Management. Pearson, 2005.
Atenció: Aquestes cites poden no estar 100% correctes.