National Cooperative Highway Research Program, Kriger, D. S., Shiu, S., & Naylor, S. (2006). Estimating toll road demand and revenue. Transportation Research Board, National Research Council.
Cita Chicago (17th ed.)National Cooperative Highway Research Program, David S. Kriger, Suzette Shiu, i Sasha Naylor. Estimating Toll Road Demand and Revenue. Washington, D.C: Transportation Research Board, National Research Council, 2006.
Cita MLA (9th ed.)National Cooperative Highway Research Program, et al. Estimating Toll Road Demand and Revenue. Transportation Research Board, National Research Council, 2006.
Atenció: Aquestes cites poden no estar 100% correctes.