Sewell Carl & Brown Paul B. (1990). Customers for life: How to turn that one-time buyer into a lifetime customer. Currency/Doubleday.
Παραπομπή σε μορφή Chicago (17η εκδ.)Sewell Carl και Brown Paul B. Customers for Life: How to Turn That One-time Buyer into a Lifetime Customer. Currency/Doubleday, 1990.
Παραπομπή σε μορφή MLA (8th εκδ.)Sewell Carl και Brown Paul B. Customers for Life: How to Turn That One-time Buyer into a Lifetime Customer. Currency/Doubleday, 1990.
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