Toymentseva, Irina A., Lilyana A. Sosunova, Vyacheslav Kornev, and P. Karpova Natalia. 2016. “Quality Management at Service Business: Theoretical and Methodological Aspects”. International Review of Management and Marketing 6 (5S):274-80. https://econjournals.org.tr/index.php/irmm/article/view/2831.