Isaenko, Anatoly Vladimirovich, and Aleksey Vasilievich Korolev. “Conceptual Directions of Public Service Quality Improvement in Public Catering Companies”. International Review of Management and Marketing, vol. 6, no. 5S, Aug. 2016, pp. 67-73, https://mail.econjournals.com/index.php/irmm/article/view/2724.