Boceski, G.: Quantitative Analysis Methods of Sales and Customer Satisfaction, Master thesis, Faculty of Mechanical Engineering, Skopje, January 2020 (in Macedonian).

Lewis, E. St. Elmo: Financial Advertising (The History of Advertising), Garland Publ., New York, 1985.

Murley, P.: Handbook of Customer Service, Gower Publishing, Ltd., 1997.

Kessler, S.: Measuring and Managing Customer Satisfaction: Going for the Gold, ASQC Quality Press, 1996.

Biswas, S.: Relationship Marketing: Concepts, Theories and Case, PHI Learning Pvt. Ltd., 2014.

Hoos, A.: The Sales Funnel Bible: How to Generate More Leads, Turn More of Them into Customers, and Do It All Faster, Easier, and for More Profit, Create Space Independent Publishing Platform, 2014.

Graham, D.: Advantage Way of Selling, Inchcape Strategic Center, 2009.

Pamln, Ca.: The Essential Guide to Mystery Shopping, Happy About, California, 2009.

Owen, R., Brooks, L. L.: Answering the Ultimate Question: How Net Promoter Can Transform Your Business, John Wiley & Sons, 2009.

TMC: Toyota Code of Conduct, Toyota Motor Europe, 2006. [11] Liker, J. K.: The Toyota Way – 14 Management Principles from the World's Greatest Manufacturer, McGraw-Hill Education, 2004.

Reicheld, F.: The Ultimate Question 2.0, Harvard Business Review Press, 2011.

https://www.thedesiredpath.com/amp/introducing-thereal-customer-funnel, (Accessed на 15.02.2019).

https://www.medallia.com/net-promoter-score/ (Accessedon 28.11.2019).