Stepanić, Josip, and Željko Cvirin. “Pregled Planiranja Smanjenja količine štetnih ispušnih Plinova”. Promet - Traffic&Transportation 8, no. 4-5 (1): 73-76. Accessed April 16, 2024. http://traffic.fpz.hr/index.php/PROMTT/article/view/820.