"As soon as people become tributaries of transport, not just when they travel for severaldays, but also on their daily trips, the contradictions between social justice and motorizedpower, between effective movement and higher speed, between personal freedom and engi-neered routing, become poignantly clear. Enforced dependence on auto-mobile machinesthen denies a community of self-propelled people just those values supposedly procuredby improved transportation."
Ivan Illich of Energy and Equity
here is another great reference:
Donald Shoup, the High Cost of Free Parking http://www.uctc.net/papers/351.pdf