1. http://www.marketingteacher.com/introduction-to-services-marketing/
2. http://www.yourarticlelibrary.com/marketing/service-marketing-definition-features-and-problem-faced-in-marketing-services/32336/
3. http://lexicon.ft.com/Term?term=services-marketing
4. http://digitalcommons.fiu.edu/cgi/viewcontent.cgi?article=1455&context=hospitalityreview
5. http://www.supplychainquarterly.com/topics/E-Commerce/20120827-direct-to-consumer-challenges-for-distribution/
6. http://www.supplychainbrain.com/content/nc/industry-verticals/retail/single-article-page/article/e-commerce-causes-major-distribution-challenges-for-retailers-and-wholesalers/
7 https://warrington.ufl.edu/centers/retailcenter/docs/papers/RevolutionInDistribution.pdf
8. IT-Based Management: Challenges and Solutions by Joia