1. Apogee Research Inc., 1990, TRIP National Transportation Survey: 1990 Poll Results, Summary Report prepared for the Road Information Program, November.
2. Baldassare, M., 1991, Transportation in Suburbia: Trends in Attitudes, Behaviours and Policy Preferences in Orange County, California, Transportation 18: 207–222.
3. Borins, S.F., 1988, Electronic Road Pricing: An Idea Whose Time May Never Come, Transportation Research 22A: 37–44.
4. Brog, W., 1991, Behaviour Begins in the Mind: Possibilities and Limits of Marketing Activities in Urban Public Transport, Paper presented at the ECMT Round Table 91, on Marketing and Service Quality in Public Transport.
5. Consumers Association, 1990, Traffic in Cities, Which Report, October, 582–585.