Kotabe, etal. (2011). International Marketing. Third Asia Pacific Edition. Milton Qld: John Wiley & Sons Australia.
Belch, G. E., & Belch, M. (2012). Advertising and Promotion: An Integrated Marketing Communication Perspective (9th ed.). New York: McGraw-Hill
Buttle, F. (2009). Customer Relationship Management: Concepts and technologies (2 ed). Oxford, UK: Elsevier