Klopotan, I., K. Vrhovec-Žohar, and E. Mahič. “Relationship Between Customers’ Loyalty and Income: Preliminary Research”. ENTRENOVA - ENTerprise REsearch InNOVAtion, vol. 1, no. 1, Oct. 2015, pp. 65-70, https://hrcak.srce.hr/ojs/index.php/entrenova/article/view/14386.