Greenberg, P. (2004). CRM at the Speed of Light (3rd.). Tata Mcgraw Hill pub. co.
Chicago-viite (17. p.)Greenberg, Paul. CRM at the Speed of Light. 3rd. New Dehli: Tata Mcgraw Hill pub. co, 2004.
MLA-viite (9. p.)Greenberg, Paul. CRM at the Speed of Light. 3rd. Tata Mcgraw Hill pub. co, 2004.
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