Zelenika, Ratko, Drago Sever, Sabina Zebec, and Bojan Pirš. “Logistic Operator- Fundamental Factor in Rational Production of Services in Multimodal Transport”. Promet - Traffic&Transportation 17, no. 1 (1): 43-53. Accessed December 3, 2021. https://traffic.fpz.hr/index.php/PROMTT/article/view/618.