Subkhan, M. F. ., I. A. . Maruta, and I. A. . Mahendra. “Quality of Service on Road User Satisfaction: Study on Surabaya-Malang Toll Road Customers”. International Journal of Social and Management Studies, vol. 4, no. 2, May 2023, pp. 186-95, doi:10.5555/ijosmas.v4i2.307.