6Murphy, J. Improving Customer Service The Mystery Shopper Approach[J]. Licensing World, 2010 (1) .
7Wilson A M. The role of mystery shopping in the measurement of service performance[J]. Managing Service Quality, 1998 (6).
8Van Der Wiele T, Hesselink M, Van Iwaarden J. Mystery shopping: h tool to develop insight into customer service provision[J]. Total Quality Management, 2005 (4) .
9Jankal R, Jankalov M. Mystery shopping the tool of employee communication skills evaluation[J]. Verslas: teorija ir praktika, 2011 (1).
10Latham G P, Ford R C, Tzabbar D. Enhancing employee and organizational performance through coaching based on mystery shopper feedback: h quasi experimental study[J]. Human Resource Management, 2012 (2) .