Gaya APA
Tunggal, A, W.
(2008).
Dasar-dasar Customer Relationship Management (CRM)
.
Jakarta:
Harvarindo.
Gaya MLA
Tunggal, Amin, Widjaja.
"Dasar-dasar Customer Relationship Management (CRM)".
Jakarta:
Harvarindo,
2008.
Text.