1. User perceptions and engineering definitions of highway level of service: an explanatory statistical comparison;Choocharukul;Transportation Research Part A,2004
2. Analysis of relationships between drivers’ satisfaction with traffic characteristics and service levels of expressways;Ishibashi;Proceedings of the Fifth International Symposium on Highway Capacity and Quality of Service,2006
3. ISO (2004). ISO 10002 (Customer Satisfaction, Complaints). The ISO Concept Database (ISO/CDB), http://cdb.iso.org.
4. TRB (Ed.). (2000). Highway capacity mannual 2000. Washington, D.C.: Transportation Research Board.
5. Quality-of-service perceptions by rural freeway travelers;Washburn;Transportation Research Record,2004