Radnović, B., R. M. Marić, V. Radnović, M. Ilić, and D. Lukač. “Marketing Research on Passenger Satisfaction With Public Transport Service in the City of Belgrade”. Promet - Traffic&Transportation, Vol. 27, no. 1, Mar. 2015, pp. 47-57, doi:10.7307/ptt.v27i1.1522.