Zang, Guangzhi, Meng Xu, and Ziyou Gao. “High-Occupancy Vehicle Lanes and Tradable Credits Scheme for Traffic Congestion Management: A Bilevel Programming Approach”. Promet - Traffic&Transportation 30, no. 1 (February 26, 2018): 1-10. Accessed April 18, 2024. http://traffic.fpz.hr/index.php/PROMTT/article/view/2300.