Putra, S. G., A. D. Wicaksono, G. Prayitno, and N. T. Hiep. “Improving the Quality of Toll Road Services to Increase Satisfaction Level of Pekanbaru – Dumai Toll Road”. Civil and Environmental Science Journal (CIVENSE), vol. 6, no. 1, Apr. 2023, pp. 24-32, doi:10.21776/ub.civense.2023.00601.4.