Harden, L., & Heyman, B. (2009). Digital engagement: Internet marketing that captures customers and builds intense brand loyalty. American Management Association.
Lua i Stíl Chicago (17ú heag.)Harden, Leland, agus Bob Heyman. Digital Engagement: Internet Marketing That Captures Customers and Builds Intense Brand Loyalty. New York: American Management Association, 2009.
Lua MLA (9ú heag.)Harden, Leland, agus Bob Heyman. Digital Engagement: Internet Marketing That Captures Customers and Builds Intense Brand Loyalty. American Management Association, 2009.
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