National Research Council (U.S.). Highway Research Board, National Research Council (U.S.). Highway Research Board. Special Committee on Electronic Research in the Highway Field, & National Research Council (U.S.). Highway Research Board. Committee on Traffic Control Devices. (1968). Route guidance: 5 reports. Highway Research Board, National Research Council.
Dyfyniad Arddull ChicagoNational Research Council (U.S.). Highway Research Board, National Research Council (U.S.). Highway Research Board. Special Committee on Electronic Research in the Highway Field, and National Research Council (U.S.). Highway Research Board. Committee on Traffic Control Devices. Route Guidance: 5 Reports. Washington, D.C: Highway Research Board, National Research Council, 1968.
Dyfyniad MLANational Research Council (U.S.). Highway Research Board, et al. Route Guidance: 5 Reports. Highway Research Board, National Research Council, 1968.