Παραπομπή σε μορφή APA (7η εκδ.)

Daffy Chris. (2001). Once a customer, always a customer: How to deliver customer service that creates customers for life (3rd ed.). Oak Tree Press.

Παραπομπή σε μορφή Chicago (17η εκδ.)

Daffy Chris. Once a Customer, Always a Customer: How to Deliver Customer Service That Creates Customers for Life. 3rd ed. Oak Tree Press, 2001.

Παραπομπή σε μορφή MLA (8th εκδ.)

Daffy Chris. Once a Customer, Always a Customer: How to Deliver Customer Service That Creates Customers for Life. 3rd ed. Oak Tree Press, 2001.