Ibrahim, Ahmad Nazrul Hakimi, Muhamad Nazri Borhan, Nur Izzi Md. Yusoff, and Amiruddin Ismail. “Rail-Based Public Transport Service Quality and User Satisfaction – A Literature Review”. Promet - Traffic&Transportation 32, no. 3 (May 10, 2020): 423-435. Accessed September 19, 2020. http://traffic.fpz.hr/index.php/PROMTT/article/view/3270.